A/N: This chapter will give you a lot of background information on Katherine. I hope it's not too much, but it's necessary to understand what's been going on. Some things will finally make sense after this ;)

ELENA

The night ended with a weird kind of slumber party. Bonnie slept in my room with me, functioning as energy source for the protective shield. Alys slept in Jeremy's bed – I was sure he wouldn't mind – and Damon and Stefan crashed on the couches in the living room. Given that it was already way past midnight when we finally made it to our respective beds, we were all still sound asleep the next morning when determined shouting and knocking at the door jumped us awake.

My room and Jeremy's gave out to the street, so there was no missing Caroline's piercing voice. "Elena! Open up! It's after twelve, and your curtains are all drawn. I know you're in. Something's happened."

If anything was likely to jerk me out of slumber, it was that line. I put on a sweat jacket and quickly hastened down the stairs. Damon had beat me to opening the door. He wasn't looking pleased. "What can be so dramatic that you're trying to raise the dead first thing in the morning?" he asked her, dripping sarcasm. "They no longer serve lattes at the Grill? Spotted someone with the same Gucci purse? Broke a nail?"

Nonplused, Caroline stared at Damon, who – after having taken off his pants and shirt for the night – was facing her in a snug fitted T-shirt and a pair of black boxers. Not to mention that his feet were bare and his hair was tousled. He looked sexy, though, especially because even disheveled and in state of semi-undress, he still oozed confidence from every pore and clearly saw no reason to be embarrassed about anything.

"Damon?" Caroline said, befuddled. "What are you doing in Elena's house?"

Given that she had missed out on recent developments, her bafflement was understandable. Her contact with Damon had basically ended with the end of their affair. She didn't know what had happened between then and his leaving town. Nothing about vampires, nothing about Katherine, and definitely nothing about Damon's and my 'something', as Bonnie referred to it. She still didn't even know that Stefan was my brother. And I couldn't tell her.

"Caroline," I said, coming to the door myself and pulling it fully open. Caroline stormed in, brushing past Damon, and remained transfixed in the hallway when she caught a glimpse of Stefan, who was slowly sitting up on the couch, wiping the sleep from his still drowsy eyes, and Bonnie, who came down the stairs in one of my PJs. Alys appeared in the kitchen door, a coffee mug in her hand and only wearing her baggy shirt.

"Just what is this?" Caroline asked, slightly annoyed. "It's past noon – you're all in a state of undress and obviously just woke up. Did you guys celebrate an orgy? Why wasn't I invited?" Given her confusion, she probably never noticed that her two unrelated questions – the first probably meant to be ironic, the second sounding slightly hurt – appeared a little odd in context.

"Uhm..." I started, but quickly found that I was having a hard time explaining it to her in words that would actually make sense.

"Well, don't bother explaining right now. I have some important news. You're not gonna believe this... Remember the animal that attacked Vicky in the woods a couple of months ago?"

Bonnie and I exchanged an uneasy glance, Damon raised his eyebrow. "We all certainly do. What about it?"

"Well, it attacked again last Friday night – a couple of teenagers who were hanging out at the clearing, drinking. One of them is dead, a second was found unconscious and brought to hospital. He regained consciousness yesterday and doesn't remember much – only that they had been three in the beginning. A girl is still missing. They believe the beast has dragged her body into the woods. The town is in uproar."

"Oh my God!" My hand flew to my mouth, Bonnie's face mirrored my horrified expression. Katherine! She was going on a killing spree again, and she wasn't even bothering to cover her tracks.

Damon's eyes darkened, his expression barely concealed his fury. "Damn her!" he muttered, going through his hair.

"Damn who?" Caroline inquired, slightly confused.

"He's concerned about an ex-girlfriend of his," I quickly explained, trying to stick as close to the truth as possible. "She just arrived here a few days ago, and – well, she's kind of fearless and has a tendency to act rashly."

"Why would she be strolling around in the woods?" Caroline asked, still puzzled. "Just tell her to stay in town – that's what the Council is advising everybody to do. Until they catch the beast. This time, they're not going to stop before they have it killed. – So, can I have a coffee now, while you tell me what this slumber party is all about?"

I ended up giving her a half-truth about Alys and I having had a girls' night and suddenly coming down with nausea and an extremely upset stomach, probably due to a mild case of food poisoning that we got from the pre-cooked enchiladas we had eaten. It was in line with the excuse Stefan had given her yesterday, canceling their double date because I had suddenly gotten sick. It was harder to find a reason for Damon's presence. I totally lied about his need to see Alys after a going through a nasty break-up and the alcohol that supposedly had played a role in drowning his sorrow. But that was about the only reasonable explanation for his overnight stay. If she had trouble buying it, she didn't let it show and just said she was glad that we were doing better now.

Caroline left after breakfast – or rather lunch. Damon shooed me upstairs to get dressed and ready to leave for a visit.

"Who are we going to visit?" I asked, having all forgotten about our plans for the day in the light of the new developments.

"Elijah. It's time we got some answers, and he's most likely to have them."

"We're coming with you," Stefan said after exchanging a brief glance with Bonnie. "Katherine was my ancestor, too. And if Bonnie's great-something-mother had her hands in this, she is also involved."

"Fine," Alys agreed, sighing. "Count me in, too. Though I bet Elijah won't be pleased, especially not when he learns about what Damon has done..."

*'*'*'*'*

Alys was right – Elijah wasn't happy at all. But none of us had expected applause anyway. Fortunately, Elijah wasn't one to get loud or openly aggressive. He didn't even judge. But he seemed deeply troubled when he heard what had brought all of us over to his place on a Saturday afternoon.

"This is what I feared would happen when Damon set foot in this town a couple of months ago," he said in a defeated tone. "I just didn't know how to prevent it."

"You knew that Katherine was in the tomb?" Damon asked, his voice dangerously toneless. I knew now that contrary to what his demeanor suggested, Damon was feeling most intensely when showing no emotions at all.

"I certainly did – given that I was the one who helped put her in there."

Alys and I shot Damon a worried glance, afraid of his reaction. Yet although his expression was icy, he stood unmoving, speaking with an even voice: "I'm reasonably sure that you're going to give me a long and convincing explanation for that. It had better be good, though, because I'm feeling a bit aggressive right now, and sometimes I do stupid things when I'm angry and upset..."

Elijah didn't seem impressed by Damon's threat. He probably knew that it was empty one. He was way older than Damon, and accordingly stronger. Which wouldn't necessarily keep Damon from doing something stupid, though, coming to think of it...

"Oh, there is an explanation, believe me," Elijah said calmly. "But you'll need to listen to the entire story. It's a long one."

"We are all ears."

Elijah sighed. Shoving his hands into the pockets of his pants he stood in front of the living room windows, staring out into the forest. "It all began in 1860," he began, digging up memories that obviously were painful to him. "I lived in Oak Rivers at the time, a small hamlet about a day's journey away from Mystic Falls, at least while the common means of transport was a carriage. I always changed places every few years, but I had already been in that village quite a while and had acquired a certain reputation as a doctor. I had a house in the forest, outside of town, and was often sought out by townspeople if medical help was needed."

"Doubtlessly because you had some tricks at your disposal that normal doctors didn't," Stefan remarked, and Elijah smiled at that. "True enough. Venesection was a commonly used method to treat any kind of illness at the time. It was win-win: A little vampire blood stirred into a healing tonic for the patient, a little bit of human blood left over after treatment for me. But I also happened to be really a good doctor."

"Granted. So how did you meet Katherine?"

"One day, a beautiful young woman appeared at my doorstep who was an out-of-towner. She was in despair – she had just recently found out that she was pregnant, after having been forced by her uncle who, since her beloved parent's death, was also her warden."

Damon gave a derisive snort. "Katherine was no orphan. And she didn't even have an uncle."

"That's correct. But I didn't know that at the time. I believed what she told me, and it was a sad story indeed. She wanted me to get rid of the baby to be able to run away and start a new life somewhere else – but on examining her, it became clear that the pregnancy was already too far advanced for that. Katherine was utterly devastated – she said she couldn't have the child. According to her, her parents were long dead, her brother had fallen in the war, and her uncle obviously was a monster. The only support she had was the little slave girl, Emily, who was not only her servant, but also her only friend in the world. I was afraid that she would harm herself and persuaded her to stay at my place for couple of days – until we had worked something out."

Again, Damon scoffed disdainfully. "Katherine was obviously a master of manipulation and an accomplished actress even back then if you actually bought that story."

"Yes, she was," Elijah agreed, looking pensive. "And I might have been a little smitten with her. She was beautiful, and charming, too."

"Yeah, just like a sea wasp jellyfish. Striking, dangerous and deadly. I'm afraid I fell for the same kind of charm, too."

"Well, Katherine ended up staying with me – helping me with my patients, taking care of some household chores and trying her best to make herself useful. I fell in love with her. She seemed such a lovely person, gentle, sweet, utterly lost. Little did I know that she was just using me."

"Did she know how you felt about her?" I asked, wondering if Katherine had ever been capable of loving someone.

"I never admitted to my growing feelings for her," Elijah said, as if confessing something embarrassing. "I wanted to wait until after the baby was born, for fear that she might feel pressured to leave in the event that she didn't return them. So while she never found out about my love for her, she did find out about my deadly secret. It had been hard to keep it from her, given that she was constantly around – and Katherine was smart."

"Maybe Emily told her," Bonnie suggested. "Being a witch, she must have figured it out on first touch."

"I'm pretty sure she did, but I don't think she gave me away. Yes, she was a witch and thus particularly prejudiced about vampires, but she also knew Katherine. I think she had come to respect me. At least she never meant me any harm."

"So – Katherine found out that she had taken up residence with a vampire... Wasn't she shocked?" I wondered.

"Not as one would have expected. Truth to tell, she acted more fascinated than scared. She must have asked me a thousand questions and basically learned all about vampirism in theory while still being a human. Looking back, I knew that she had already decided there and then that she wanted to be changed. For her, being a vampire signified power – something she had always felt attracted to. She probably would have convinced me to change her out of love, but things took a different turn when she went into labor.

The baby was early and the birth was complicated. I had never felt so helpless before. There was nothing Emily or I could have done. We managed to save the baby by giving her my blood, but the same didn't help Katherine. Her placenta must have ruptured, causing massive internal bleeding. She was fading fast under my hands. While she was still conscious, she begged me to change her – to make her live. For her daughter, who didn't have anybody else in the world. And so I complied."

"You still had no idea that Katherine was leading you on..."

"No, not at the time. But Emily did. So she took some measures of precaution shortly after it became clear that Katherine would make it through the change... Something I didn't learn about until much later."

"What measures?" Bonnie enquired, probably suspecting that this might be the explanation we had come looking for.

"I'll be getting to that," Elijah promised and continued: "After her transition, Katherine was indeed changed. Not so much physically, for she had been beautiful even before. But emotionally. She finally let her mask drop, and lost all beauty in my eyes. She didn't waste a single thought on her baby daughter. I had kept the girl – whom I had named Caitlin – safely away from her, so that she wouldn't kill her in the volatile state she was in so shortly after her transformation. I had hired a wet nurse to take care of the baby. Unfortunately, Katherine took care of the wet nurse."

"Oh my God – how could she do that?"

"As much as that shocked me – I knew accidents like that could happen and blamed myself for not having been more watchful. I might have forgiven her even for that – if she had shown any kind of regret, shock or remorse. But she was indifferent, even totally cold about it and just said that I could always get a new one.

That's when I finally saw her for what she really was. Heartless and uncaring – a monster that I had created. Maybe I should have killed her on the spot, but I had never had a heart for that. So I just told her to leave."

"Which Katherine obviously had planned for right from the beginning."

"Yes. On learning that an abortion couldn't be done, she had decided to stay at my place, have me help her deliver the baby and eventually go back home – without the child. She had used me shamelessly in her scheme. I still didn't know the whole truth at the time. I knew she was going back to her home town of Mystic Falls, finally having nothing to fear from her uncle, who wouldn't ever be able to hurt her again.

I only learned two years later that there had never been an uncle, nor a rape, and that Katherine wasn't an orphan. She was just a hot blooded young woman who had been too easy to get and had suffered the consequences of her irresponsibility. At that time, her parents were negotiating a wedding contract with the most influential person in her home town: the mayor. An abortion had seemed the easy solution. When that didn't work, she thought staying with me would be a fairly comfortable plan B."

"Did her parents even know about any of this?"

"No. Katherine wrote them a letter shortly after her sudden disappearance from their home – claiming that the prospect of marriage had scared her. She told them she was staying with an elderly aunt of her friend Pearl in Atlanta, who was sickly and needed help. It was only going to be for a few months – until her son, who was fighting in the war, would come back and make other arrangements. In the meantime, her parents should proceed however they wished in finding her a husband, she would gladly accept whoever they elected.

Katherine, now a newborn vampire, slender and childless and safe from ever getting in a compromising condition ever again, headed back to Mystic Falls to become the future wife of Benjamin Lockwood."

"Who probably was hoping his young wife would soon bear him an heir..." Damon added. "Just that all his efforts were wasted on her. Well, not entirely wasted, but definitely not going to get him what he wanted. That's probably one of the reasons he got rid of her."

"Well, he remarried later on and became a proud father of five. The Lockwood family still thrives."

I looked back at Elijah. "And you took in Caitlin and rightfully adopted her..."

"I raised her and loved her as if she was my own. It was the best decision I ever made in my life, and the only greater good that came out of the whole affair. Caitlin, unlike her mother, was such a sweet girl, and I almost managed to forget about Katherine completely. Of course, I had to tell Caitlin the truth about her mother and about me at some point – she couldn't help noticing that her daddy never seemed to age while she grew up."

"How did she take it?"

Elijah expression softened. "She said that I was the best father she could ever have wished for and that it didn't matter to her. She had a great, caring heart. That's when she started to write her diary, putting down everything that she had learned and everything that she found out later."

"Did she never ask you to turn her, too?" I wondered.

"She might have considered it at some point. But then she fall in love with a very nice, young man, and wanted to have a family of her own. She got married to him and gave birth to four children. She decided to stay human. We always stayed in contact, though mostly by correspondence. I visited her many years later, telling her husband and my grand-children that I was Caitlin's nephew. But Caitlin had shared my secret with her daughter, already a lovely young woman at the time. It had started a tradition. Caitlin had made sure with her diary that I always kept having a family, even long after she and her daughter had passed away. Until today, there has always been a daughter, always one family member who knew who I was. And I have always been keeping an eye on Caitlin's descendants."

"Are you saying my mother knew who you were?" I asked, not sure how I felt about learning another secret that had been kept from me.

"Yes. She had known for a very long time."

I threw Stefan a questioning glance, but he slightly shook his head, telling me silently that he hadn't known that, either. Most likely my mom had wanted to stick to the tradition and tell her daughter – except she died before she had the chance to do so. Still, one thing didn't quite add up. "But I found nothing about you or Caitlin in her diaries. And there was no diary of Caitlin's, either."

"Because the most important one, the one that she kept especially for you, I have not given to you yet."

"Why not?" My voice broke, and I felt tears threatening to rise. I couldn't help feeling betrayed. This secret was such a huge part of my family – it had been kept from me, and it would have changed everything. I was the only one who really had fully suffered the impact of Stefan's death. While my parents had to accept that he could no longer be a part of our family, they could take comfort in knowing that he was still alive. For me, his death had been real.

Their death had robbed me not only of their presence in my life, but also of every opportunity for my mom to share this really important part of who she was with me. Elijah had been the only one capable of passing on her legacy to me. And yet he hadn't. How could he have kept it from me?

"Because of Damon," Elijah said softly, his voice full of regret. "Emily had told me about him and his plea to save Katherine in turn for saving her children. She knew he was desperately in love with her. And Emily kept his secret, never told the council members that he was a dark one, too. For 150 years, until that comet returned, the tomb would be safe. But when Elena returned to Mystic Falls last year – looking exactly like Katherine – I felt dread. It was like a bad omen. And then Damon suddenly turned up, too, and we had all the ingredients for disaster. I was afraid that he would find out about Katherine and set her free. That's why I tried my best to keep you both in the dark."

"Gee – thanks!" Damon said spitefully. "Guess what – I found out without your help. I went through the birth certificates. It wasn't so hard to trace Elena's line back to Caitlin. You could have saved me quite a few days in stuffy offices going through church records."

"You said you had almost forgotten about Katherine after she left you and her child," I pointed out to Elijah, before he and Damon could start to argue. "But you still helped put her in the tomb. So there must be more to the story... You've still been missing out the part with Emily's secret."

Elijah nodded, looking unhappy. But he continued. "One evening in 1864, about two years after Katherine had left us, Emily suddenly reappeared at my doorstep and told me what had become of Katherine: That she had indeed married Benjamin Lockwood, but that she was cheating on her husband and had numerous affairs. She also had turned quite a few people into vampires. The virus was spreading like an infectious disease, creating havoc in Mystic Falls and being the cause for a number of very suspicious deaths. Influential people had become aware of the vampire problem and had formed a secret council that saw its sole purpose as ridding the town of all vampires. And according Emily, they were getting dangerously close to carrying through with their plan."

"Why would she even tell you that?"

"Good question – I failed to see why this should concern me, too. Until Emily shared her secret with me. She had been a personal slave to Katherine for a long time and knew her very well. Not that Katherine had ever been cruel to Emily herself. Quite on the contrary, she even treated her as a friend – as long as Emily was doing her bidding. But there was always the threat in the air, that, if she should stop being loyal to Katherine, Emily's family would suffer. So Emily had three good reasons for doing what she had done: The prospect of being a slave to an immortal vampire was one thing, to have some leverage was another. But she was also a witch, and witches were all sworn to one common duty: guarding the balance of nature.

Bonnie blanched. "What had she done?"

"Right after Katherine's transformation, Emily had tied her immortal life to that of her daughter, thus making her mortal again. Katherine's life would end the minute her daughter died. That gave Emily the ultimate power over Katherine – all she had to do was kill Caitlin and Katherine would go too.

"So she had come to kill the child?" I asked, shocked to thing that anyone could be so callous.

"On the contrary. Emily wasn't evil. She couldn't bring herself to hurt an innocent child. She had come to save Caitlin's life, for the blood ties worked the other way round, too. If Katherine was murdered, Caitlin would die as well. And Katherine's potential killers were getting dangerously close. In order to save her, Emily had come up with a plan that would keep Caitlin safe and also put an end to Katherine's evil shenanigans in Mystic Falls. She was only capable of doing that because of a cosmic event that reoccurred only every 150 years, and which would give her the power for the ritual. She sealed Katherine into the tomb by drawing on that power, and using Caitlin's blood as a key. Thus, the only way to ever reverse the spell would be the very same circumstances as when the spell was cast – by using the blood of a human descendant."

"So – it was all coincidence? Elena, a long way down in the line of her descendants looking like Katherine, Bonnie becoming a witch, and Damon deciding to come back without even knowing about the tomb?" Stefan asked, obviously still trying to process what we all had learned.

"No," Bonnie said in somber voice. "That's just how magic works. Every spell creates its own loophole – it's all about balance."

"But Caitlin is long dead," Alys put her finger into the little hole in the logic. "Shouldn't her death have made Katherine die, too?"

"Strictly speaking, Katherine was neither alive nor dead while in the tomb. She was in death sleep, which ironically, made her able to survive Caitlin's death. Obviously, the spell didn't die with her, either. It was passed on through the bloodline – and thus ultimately transferred to Elena."

"Are you saying my life is forever tied to Katherine's?" I asked in utter shock. Stefan's expression mirrored mine.

"I'm afraid that's exactly how it is," Elijah said, looking unhappy.

Damon's face showed no emotion at all, but his voice sounded lethal. "So apart from the obvious problem that we can't kill Katherine without killing Elena, there is an added danger: Someone intent on killing Katherine might find a much easier target in Elena and try for that approach?"

Again, Elijah nodded. "I'm sorry. I wish it had never come to that. But I see now that it was bound to happen. Like Bonnie said, it's all about balance."