Disclaimer: I don't own ER or any of these characters, etc. or the lines I've taken from the show (there's quite a few in this one).

I hope the lack of reviews for the last chapter doesn't mean that people aren't reading. But I'm a fan of this story, so I'm persevering!

This is where the Marsan stuff really starts to kick off so enjoy :)

Some Mistakes Are Hard To Rectify

Mark's life was not getting any easier. Christmas had come and gone. They had welcomed the New Year. Rachel was now back at school and he was in regular contact with her teachers to keep track of her progress and behaviour. So far, so good, but despite an improvement in her grades, the atmosphere was still tense at home. Rachel and Elizabeth were constantly bickering and Mark was being moaned at by both parties. Ella had noticed the stress in all of them, which upset her. Sometimes – a passing thought that quickly went away – Mark wondered what life would be like on his own, without his family. No arguments, no stress; a simple life. This thought usually appeared in his head during one of the many heated rows between Elizabeth and Rachel, while Ella screamed for attention in the background. A feeling of incredible guilt usually followed, and Mark would make a conscious effort to make up for it, willing such a thought to disappear. It didn't.

Another thought that wouldn't leave him alone was Susan. She was constantly on his mind these days – and the nights too. The old feelings he knew he had kept buried deep inside were fighting to resurface, and Mark was using everything he could to keep them away. Falling in love with Susan wasn't an option; it wouldn't fair on any of them. But that didn't stop his mind from wandering to her face – those green eyes, that blonde hair – whenever it had the opportunity.

Mark pushed around the cold fries that lay on his plate in front of him. He was on his lunch break and hiding from the buzz of the ER in Doc Magoo's. Work was his only haven at the moment, where he could get lost in his patients and their problems, and momentarily forget his own. His pager beeped in front of him and Mark contemplated ignoring it. His conscience got the better of him. He pulled his cell phone out of his pocket, hoping that whatever it was could either wait or be dealt with over the phone. He dialled the number of the ER and waited with an impatient sigh for someone to answer. He started to tap his finger on the table.

"E.R."

"Randi, it's Mark. Did someone page me?" Mark asked, the impatience in his voice apparent.

"Oh, Dr Greene, um…"

Mark could hear whispers in the background. He frowned.

"Dr Greene? It's Abby."

Mark knew immediately from the tone of her voice that something was wrong.

"I'm sorry, your daughter has just been brought in with a suspected ecstasy overdose," Abby said quickly.

Mark didn't bother to answer. He jumped up from the table and rushed out the diner, running across the road to the hospital so fast his feet barely touched the ground. His mind was a whirlwind of questions. What happened? Was she ok? Where did she get ecstasy from?

"Where is she?" he yelled when he entered the ER.

"Trauma one," Randi called after him, watching him race down the corridor.

Mark reached the trauma room and saw a group of doctors and nurses crowded around. He crashed through the doors and almost collapsed from shock at what he saw. He was expecting to see Rachel lying in front of him; nothing prepared him for seeing Ella lying helplessly on the gurney. Elizabeth was stood next to her, watching as her friends and colleagues worked to save her daughter and questioning every action.

"Oh my God," Mark cried. "What the hell happened?"

Elizabeth looked up at him. Her eyes were a mixture of fear and anger.

"Rachel had ecstasy in her school bag. Ella got hold of it and swallowed it," Elizabeth spat at him.

Mark moved around to the side of the gurney, next to Elizabeth. Kerry was the other side, barking orders in her usual manner, all too conscious of who the patient in front of her was.

"She's in SVT," Haleh said.

"Let's get the crash cart," Chen said.

"What?" Mark questioned.

"She's hypoxic, with pulmonary oedema in SVT," Chen explained herself, following protocol.

"No!" Elizabeth cried.

"We have to," Chen said, emphatically.

"Her SATs are down to 90," Chuny said.

"Let's get her up to 15 litres of O2," Chen said, looking desperately at Kerry for intervention.

"Mark, Elizabeth, you have to let us work," Kerry pleaded with them. "I know this is your daughter, which is why you should step away. Let us do our job."

Mark and Elizabeth were pushed aside as they watched their daughter fighting for her life. Mark prayed silently, willing God to do everything he could to make her better. All of a sudden, the monitors started to go crazy next to them.

"Pulse-ox is down to 88," Chuny read.

"Her lungs are full of fluid, lets get 15 of lacex," Kerry ordered. "We need to intubate."

"No!" Elizabeth cried again. She couldn't believe this was happening. "Give the diaphoretics a chance to work first."

"Elizabeth, she's in respiratory distress," Kerry said. "We have to intubate her now."

Mark and Elizabeth fell silent. There was no point in arguing with Kerry, they knew she was right. Their judgement was clouded. Any other baby, and they would have intubated by now.

"0.2 of atropine and 15 of lidocane," Kerry ordered. She put the tube down Ella's throat and watched as her vitals started to improve. An air of calm fell over the trauma room. Finally, some good news.

"Heart rate is down to 100, pulse-ox is 99," Chuny said.

Mark and Elizabeth stepped up to the gurney.

"It's ok, baby, it's ok," Elizabeth said softly.

Mark watched, breathing a sigh of relief.

"The PICU is ready for them," Haleh said, after coming off the telephone.

"Ok, let's move her," Kerry said.

Mark and Elizabeth followed as Ella was pushed out of the trauma room and towards the lifts. At the admit desk, Mark spotted Rachel being comforted by Susan. Elizabeth glared at him, as if reading his mind.

"I'll follow you up," Mark said, nodding his head in reassurance.

He walked towards the desk. Rachel and Susan both looked up at him.

"Dad?" Rachel questioned, nervously.

"Rachel, where have you been?" Mark asked, angrily.

"I was just waiting outside. Is she ok?" Rachel asked.

"No, she's not ok," Mark said. He was too mad to be sensitive to her feelings.

"I'm sorry," Rachel said, her voice taking a babyish tone.

"You're sorry?" Mark yelled.

"Mark…" Susan tried to interrupt.

"Stay out of this," Mark warned.

Susan stepped back, knowing that it wasn't her place to get involved.

"You bring drugs into our house and leave them out for a baby," Mark started to lecture.

"They weren't mine," Rachel interrupted.

"Stop lying," Mark said, frustrated.

"I'm not. They're just for a party, I wasn't even sure if I was going to take them," Rachel defended.

"Well your sister did."

"She's going to be ok though, right? It was just one pill," Rachel said.

Her naivety arose even more anger inside of Mark.

"Are you really that stupid? Ella is 9 months old. She almost died," Mark's voice was getting louder.

"Dad, don't," Rachel pleaded.

"Don't what? Don't call you a liar? Because that's what you are, Rachel. You promised me you weren't doing drugs," Mark screamed at her. He didn't care that everyone around him was watching.

"I'm sorry," Rachel cried, tears starting to fall down her face.

"She could have long-term brain damage, learning disabilities, low IQ, memory impairment. She could still die," Mark continued.

"Please, dad, I'm sorry," Rachel cried, moving towards him, hoping that he would embrace her. "I'm sorry."

Mark moved back, a look of disgust on his face. "Go home, Rachel. I don't want to see you right now."

Mark spun around and stalked off, as Rachel dissolved into tears. Susan, who had been watching this scene from a distance, followed him.

"Mark," she called.

He paused. Anyone else, and he would have carried on.

"Don't do this," Susan pleaded.

"I need to get back to my daughter," Mark said, his voice flat.

"What about Rachel? She's your daughter too," Susan said.

"I know that. Don't guilt-trip me, Susan. She brought drugs into my house and she's put Ella's life in danger," Mark said, incredulously.

"I know. You're mad, and you've got every right to be. But please don't walk away from her," Susan said, irritated.

"What do you want me to do?" Mark yelled.

"I want you to be her father!" Susan yelled back.

Mark sighed angrily. "What gives you the right to have a go at me? Maybe when you have your own kids, you'll be in a position to lecture me."

As soon as he said it, he knew he had gone too far. Susan looked at him in disbelief.

"You son of a bitch," she said, walking off.

Mark sighed. Shit. He made his way upstairs, cursing himself for being such an idiot. Of all the insults he could have thrown at her, that one had overstepped the mark. He tried to put it to the back of his mind and concentrate on Ella. As he watched his daughter being ventilated by a machine, he wondered how many more cruel tricks life could throw at him.

Susan had spent the afternoon burying herself in her work. Everyone in the ER had heard about her altercation with Mark, but no-one had dared to ask her what it was about. She was glad; it wouldn't have been an easy explanation. She was still shocked that Mark had thrown the worst moment of her life in her face, without hesitation.

Rachel had spent the afternoon in the lounge, circling the table restlessly and watching the activity of the ER. Susan had checked up on her occasionally, to make sure she was ok. And to make sure she was still there.

Susan sighed, as she scoured through the rack of waiting patients. She didn't notice a body come up behind her until it spoke.

"Susan."

She recognised Mark's voice instantly and turned around slowly. She couldn't bring herself to meet his eyes, and instead focused on his restless feet.

"I'm so sorry," Mark said. His voice was full of remorse.

"I'm going to take Rachel home with me tonight," Susan said, ignoring his apology. "She shouldn't be home alone."

"Susan…"

"Is that ok?" She finally lifted her head and met his eyes. His were full of sadness; hers, anger.

Susan softened, remembering what he was going through.

"How's Ella?" she asked softly.

"Her vitals are stable and she's SATing well on 50%," Mark answered, a hint of optimism in his voice.

"And Elizabeth?" Susan asked.

"She's ok. She tired, but she refuses to leave Ella's side," Mark answered. He sounded tired. "Susan, I'm so sorry about what I said. I was angry, and I vented that anger on you and I was wrong."

Susan shook her head. "It doesn't matter," she dismissed him.

"Yes, it does. I was out of line, and there's no excuse for what I said," Mark said.

Susan nodded and Mark took it as a sign that she had accepted his apology.

"Where's Rachel?" Mark asked.

"In the lounge. I finish in half an hour, she can stay at mine tonight," Susan offered. "You should talk to her before we leave."

Mark shook his head. "I can't. I'm sorry, I know you think I should, but I can't. I'm too angry, Susan, and I'll just say more things I'll regret."

Susan nodded, understanding.

"I should get back upstairs," Mark said. He started to turn, but paused. "Thank you."

"You know where I am if you need anything," Susan said.

Mark nodded and went back upstairs to the Paediatrics Intensive Care Unit, where Elizabeth was still hunched over the bed where Ella lay. There were tubes coming out of her, giving her air and medication, and wires attaching her to machines. She looked lifeless and it broke Mark's heart. He sat down silently next to Elizabeth, putting his arm around her. She shrugged him off.

"You've been to see Rachel?" she asked coldly.

"I went to check on her, yes," Mark answered. "She's staying with Susan tonight."

'Saint Bloody Susan,' Elizabeth thought with contempt.

"Good," she said aloud. "I don't want her anywhere near my family."

"Elizabeth…"

"I mean it, Mark. I don't want her in my house and I certainly don't want her anywhere near Ella," Elizabeth said angrily.

"She's my daughter," Mark said.

"And so is Ella," Elizabeth said, her voice raised. She caught herself and softened her tone. "She nearly died. She still could die or suffer long-term damage."

Tears started to fall down Elizabeth's cheeks again and she wiped them away quickly, frustrated.

"I know. I blame Rachel too, but you can't ask me to turn my back on her," Mark said.

"That's exactly what I'm asking," Elizabeth said spitefully. "Either Rachel is on the next plane to St Louis or…"

"Or what?" Mark interrupted.

"Or I'm not bringing Ella home," Elizabeth finished. "And until you can show some loyalty to us, you can get out."

Mark stood in shock, unable to comprehend what Elizabeth was saying.

"What?"

"Get out!" Elizabeth cried.

"Elizabeth…"

"GET OUT!"

Elizabeth's screams caught the attention of the security guards, who came towards them.

"Is everything ok here?"

Elizabeth's face wore a hard expression, refusing to back down. Mark knew when he was defeated; he had never been very good at standing up to Elizabeth. He backed away in disbelief and stood outside in the hallway, contemplating what to do. He knew that the security guards were watching him and until he did what she asked – until he had chosen one daughter over the other – Elizabeth wouldn't allow him back into the PICU. He made his way downstairs and outside, avoiding the ER. He couldn't handle the questions and the sympathy right now. Instead, he went to find the only thing that would bring him comfort right now.

Susan stood watching Rachel as she washed the dinner plates. She had a hard time believing it was the same girl who had once been so sweet and innocent. Rachel caught her staring.

"What?" she said, automatically defensive.

"Where did you get the drugs?" Susan asked.

Rachel studied Susan's face. There was no anger or aggression. It was a simple question.

"A guy at school. There's a party on Saturday night and some of us were thinking of taking some," Rachel answered honestly. She sighed and sat down at the kitchen table.

Susan sat down next to her. "Why?"

Rachel shrugged. "I don't know. I wanted to. I just wanted to go out and forget everything."

"Rachel, do you remember my sister, Chloe?" Susan asked.

"Kind of. She was always bubbly and funny," Rachel answered, smiling slightly.

"She was always high," Susan said. "Or drunk. She lived her life as one big party. Even after Little Susie came along, she still went out and got wasted. She didn't care about leaving a baby home alone, she just wanted to go out and forget everything for a while. But you know, every morning when she would wake up, everything she was trying to forget was still there. You can't escape life using drugs and alcohol, Rachel. It's the coward's way out."

Rachel sat taking in everything that Susan was saying, grateful that, for once, she was being spoken to like an adult rather than a child.

"He's never going to forgive me, is he?" Rachel asked quietly.

"Do you blame him?" Susan questioned.

"No," Rachel answered, a tear falling down her cheek. "I really screwed up."

"Yeah, you did," Susan said. She put her hand on Rachel's. "But give him time."

"Thank you," Rachel said.

"You should go get some sleep. I've made up the bed in the spare room and there's a pair of pyjamas in there for you. We'll stop by your house in the morning before I drop you off at school," Susan said, her motherly instincts taking over.

"I have to go to school?" Rachel asked.

"I've got to go to work. Your dad will be at the hospital," Susan answered.

The tone of her voice told Rachel that there was no point in arguing. She got up and disappeared into the bedroom. Susan started to put away the dishes when there was a slow knock at the door.

She looked through the spy hole and saw Mark stood on the other side, leaning against the door frame. She opened the door.

"Hey, I wasn't expecting you here tonight," Susan said, concerned. "Is everything ok?"

"No," Mark answered, staggering in.

Susan sighed. "You're drunk." It was a statement, not a question.

Mark fell onto the sofa. Susan came and sat on the table in front of him.

"Why aren't you at the hospital?"

"Elizabeth made it clear I wasn't welcome," Mark slurred.

Susan frowned. "Why?"

Mark leant forward to whisper. "Rachel." He fell back into the sofa again.

Susan sat looking at him. "So you thought that getting drunk would solve your problems?" she asked incredulously.

"Nope," Mark said. "But it makes me feel a whole lot better."

Susan shook her head. "I've just told Rachel that you can't use drink and drugs to run away, and you turn up like this. I can't believe you, Mark. Why are you doing this?"

"Why not?"

"Because people need you. Ella, Elizabeth, Rachel," Susan said.

"No, they don't. They'd all be better off without me," Mark said, dropping his head.

"Mark, stop this. All this self-pity isn't doing anybody any good," Susan said, frustrated that there seemed to be nothing she could say to lift his mood. Mark put his head in his hands and began to rock, back and forth.

"I'll make you some coffee," Susan said gently. "You need to sober up and get back to the hospital."

"Elizabeth doesn't want me there," Mark said. "She wants me to choose. It's either Rachel or Ella."

"What?" Susan couldn't believe what she was hearing.

"It sucks, huh?" Mark said, shaking his head. "It's not losing Elizabeth that scares me. I think our relationship has been over for a while. But without Elizabeth, I'm scared there'll be no Ella."

"Oh, Mark," Susan sympathised, putting her hand on his shoulder and squeezing it, comfortingly. "I wish there was something I could say or do."

Mark looked up at her. Maybe it was the alcohol that gave him the courage to do it, or the need for comfort and love; but he leant forward and kissed her. Susan was so surprised that she didn't react straight away. Mark took it as a sign that he was welcome to continue and he brought his hand up her neck, pulling her towards him. Suddenly, Susan pulled back.

"What the hell are you doing?" she cried, horrified at what had just happened.

"I…I'm sorry," Mark stuttered. "I thought…I…"

He got up and stumbled towards the door. Susan didn't move, frozen to the spot. Mark looked back at her.

"I'm sorry."

Mark opened the door and rushed out of the room. His chest felt tight and he rushed outside, gasping for air.

'What the hell have I done?'