Summary: For years, it was their little secret. But ten years has passed, and it's becoming increasingly difficult to hide.

Pairing: Bim/Lumi, Linzin, Pemzin

Rating: T

For years it had been their secret. Their little secret. Secrets, if you will.

Their contact was minimal, they made sure of it; any sort of suspicion could blow their cover. He knew she didn't love him that way, she couldn't love him that way, there was no such thing as jumping from one brother to the next; while what they had created benefited them both greatly, it was not something they shared together.

That's why six months after the beginning of the Republic City Restoration movement, when his fleet returned, she was shocked to see him calm. Too calm. Bumi was never calm.

"Hello brother," Tenzin looked stuffy and rigid as usual. Sometimes Lin wondered how Tenzin could even be an air bender, didn't he need to be free and 'be the leaf'? She remembered when Aang had tried to coax Tenzin out of his gentle shell, Tenzin's airbending abilities had bloomed late into his pre-teens, for a while they all thought that he was just a non-bender like Bumi.

"Sup." Bumi was relaxed and always at ease; even though he had a few years on Tenzin, he didn't look a day over forty. It really was amazing how young he looked, and sometimes it made Lin feel embarrassed how the stress of being Chief of Police had grayed her hair. "Hey Linny." His wild eyes shifted to her and he grinned, batting a playful wink at her. His body language was far too relaxed, hell, the last time he'd made one of his grand entrances he'd been standing on top of the ship, screaming with victory and glee. So what made this time any different?

"You're unusually...calm." Tenzin murmured, his lips pondering on the last word. Ah, so it hadn't been just her who had noticed. His eyes examined Bumi carefully, as if he was trying to get ahead of his older brother in some invisible, inclusive game that only the two of them could partake in.

"I brought Kya and Mom. And a-uh, few others." His eyes trickled over to Lin, and his lips pulled back to reveal a white grin. At that point in time, Lin's heart stopped.

He didn't.

He didn't.

She hadn't seen them in almost a year. In fact she'd been due for her two weeks of vacation time, where she would travel down to the small island that the United Forces held their main base at.

"Bumi-" Lin's voice was panicked and her minty eyes were wide with horror.

"Taji! Koda!" Bumi's voice barked at the gangplank. "Come here boys!"

Lin's eyes flashed at the gangplank, her heart stilling at the two figures that stood tall. Only eleven, but still quite tall.

Taji was the older one, by five minutes and fifteen seconds. His skin was fair like hers, and his hair as dark as midnight. His eyes were a vibrant mint green.

Next was Koda. His skin was tanned, like Bumi's, his hair wild and light, also like Bumi's. But like his brother, he shared the vibrant mint irises.

Lin's eyes flashed to Tenzin as his eyes scanned over the boys, and she was terrified as his peppery eyes snapped over to meet hers.

"Bumi, what is this." It wasn't a question, it was a statement. Tenzin knew the answer, they all did, but he needed to hear it out loud. The eyes gave it all away.

"Ma!" Lin's head turned as Taji ran to her, his arms weaving around her to yank her close. "I missed you." He had a goofy smile, like Bumi, and she could tell that he and his brother were little troublemakers.

"LIN." Tenzin's voice began to lose patience. "A word please." His voice was low and gruff, threatening in the slightest form as he stared at her. Lin's hands were raking through Taji's hair absentmindedly, and she pursed her lips, peeling herself from her son as she followed Tenzin further down the dock.

"What. In the world. Are those two boys." Tenzin's voice was sharp and demanding, causing Lin to take a defensive stance. The way he was talking to her brought up a bitter taste in her mouth that she swirled around and spat to the side.

At that moment, memories flashed to her. Tenzin's break up with her, his immediate get together with Pema. The reasoning? Pema was a non-bender, she lived the life of an Air Alcoyte. She held the perfect womb for an airbender. Lin however, she was from a powerful earthbending line, the dominance of earth would trump his airbending genes once and for all. Avatar Aang had been deceased for a few years, and Tenzin truly was the last airbender. He couldn't risk it.

Feelings of desperation and anger had flooded her. She had wanted kids too, she had wanted them just as much as him and she'd wasted thirty nine years on attempting to procreate with him. After it happened Lin didn't cry, she sat in silence and frustration. Then Bumi came over with hard liquor, and in her lowest moment, Lin had opened herself to the greatest change possible.

"I can give you children." He had offered in a drunken slur. "I mean, you may not want them now, at the peak of your career, but I can take care of them. They'll love you just as much. It's just your reproductive prime is waning, and fast."

Bumi had always loved her. He had pined after her while she attempted to fix loose ends with the beginning of the end of her relationship with Tenzin. Not seriously of course, just simple little gestures here and there. But it had always been clear that he harbored un-reciprocated feelings for her. However, even drunk as a sailor, she knew he was right.

So they tried.

The next morning, they woke up naked and horrified. Well Lin was horrified. She wanted children, but not this way.

"Relax," he had told her in an attempt to ease her conscience, setting a warm hand on her shoulder. "I doubt you're pregnant. Remember, you're forty. What are the odds?"

The odds weren't likely, but it happened.

And then she found out they were twins.

For the next nine months Lin Bei Fong stayed on the United Force's base, claiming to be working with the metal benders. And she had been, a strong man named Taji whose wife, a waterbender from the North Pole, would be delivering the baby in secret.

Taji and his wife Harukka were both humble and generous, opening their home to Lin so that she could have accommodations that didn't draw unwanted suspicion.

One day a mechanic issue gone wrong took Taji's life; while his gentle wife mourned, Lin knew instantly that if she bore a male, he would inherit the name.

Throughout the entire process, Bumi had been beautiful and wonderful. He showed her that with as much fearlessness and insanity that he bore on the battlefield, he could match equally with compassion and care. For a moment, Lin swore she was falling in love with him. But then painful reality came back into play and she realized that he was the brother of her ex-lover. She was boring the child to her ex-lover's brother. It felt so wrong but she was in too deep by then, and the anticipation was killing her.

Harukka was so wonderful during the process of labor, so wonderful in fact that Lin swears to herself if she ever had to repeat the past, she wouldn't do it any other way. Even if Katara had been an option. Taji was born, boring resemblance to Lin, and Koda was not far behind, showing all of Bumi's features, apart from the eyes.

They were perfect.

Lin stayed a few months longer, then she returned to her duties at Republic City. Apart from when she was able to witness them herself once a year, discreet telegrams from Harukka informed her on the growth of the boys, as well as their capabilities.

Taji was an earthbender, a strong one. Koda was a non-bender.

Lin stared at Tenzin, her eyes sharpening as she arched her back into a straight position. "They're my boys." She answered curtly. Tenzin's eyes bulged and she could tell he was about to ask how. "It was an accident. A wonderful accident."

"They look older than Jinora."

Lin's eyes flashed. "You took over a year to get Pema pregnant." She reminded, her teeth gritting slowly.

"So you decided to run off with my brother and get pregnant?" Tenzin demanded. His eyes were smoldering with anger and Lin swore there was a mixture of pain as well.

"Don't you look at me like that," Lin said. Her voice was a low growl and she clenched her fists. "You know I only had eyes for you, even if hehad eyes for me. You knew I wanted children, but that didn't stop you from stringing me along until it was almost too late for me." Her voice was hushed but powerful, and her eyes showed no remorse or regret in her actions. "You're angry because Bumi gave me what you never wanted to, that he loved me like you never could, and you're angry because you regret your actions in the past." Her hand swiped to the side as if to add emphasis. It seemed to strike a chord with Tenzin, and his jaw tightened.

"I don't regret anything." Tenzin's eyes locked onto hers.

"Good." She said, her voice a low murmur. "Neither do I."

The two turned on their heels, returning to the others as Kya and Katara descended down the gangplank.

"Bumi, tell me." Katara seemed a bit exasperated. "Why did you need us all together?" Her blue eyes searched over the twins, taking them in for the first time. Lin pursed her lips, anticipating that he was about to announce Taji's earthbending skills to the group.

"I brought you all here mother, because I wanted to introduce you to your second set of grandchildren. My children. Lin's children." Bumi didn't even wait to get the confirmation from Lin that it was alright to announce their secret to the world, though the only person it mattered to keep it from was Tenzin. Katara's eyes drifted over the two boys. "This is Taji, an earthbender. Powerful like his mother and grandmothers." His hand set on the shoulder of Koda. "And this is Koda. They're both my pride and joy, but you'll find that Koda's a bit more special than the average kid.

"Taji and I are both extremely proud of him, and I hope you will be too, Lin." Bumi's eyes looked up at her pleadingly. She saw the look and recognized it. It had been over a decade, he wanted her, he wanted her to give him a shot to prove that he could be the best that there was for her.

"Because everyone said you couldn't do it. That you wouldn't be able to have children past your thirties, that you wouldn't be able to give Tenzin what he wanted. And I just want you to know that even though we aren't able to be a family, at least not yet, that I believed in you all along." His crooked smile showed, and Taji's flashed across his face to match. "Taji, would you like to give the word of honor?" He nudged the son, whose hands clasped with his brothers. Taji opened his mouth and his strong, confident voice bellowed the five most earth shattering words Lin could ever hear.

"Koda is an air bender."