A/N: Joining Tumblr has made my Loki and Thor feels skyrocket. Here's the result of the need to get some of it out of my system.

Cover image art by karaii on DeviantArt. Used with her permission.

As to Thor's age during the flashbacks, I'll call him the equivalent of about five.

Disclaimer: I do not own Thor.

A Promise of Protection

Loki had home, back in Asgard for almost a year now. He still did not think of it as home, sitting in this room under the palace, feeling shut away and ignored. The room was comfortable, and filled with books for him, but he still viewed it as a prison. There was a single thing that lessened his anger and brooding.

Thor visited him every single day. He came with smiles, comforting words, and hugs (Loki, while he never returned them, had long since given up trying to fight against them). In the beginning he had done nothing but fight with Thor, but that was coming to an end. He didn't speak much, but he no longer fought. He was honestly tired of it.

Thor considered today's visit to be crucial. Not only had Odin told him that he was going to release Loki soon, but Thor had decided today was the day that he would tell Loki something he probably should have told him long ago, but he had never thought he needed to. He had known Loki needed to hear it after this whole mess had occurred, but had decided to wait until he was more receptive.

Thor didn't miss the way Loki's head snapped up when Thor entered the room. Loki would never admit it, but Thor knew that Loki had begun to count on, and perhaps look forward to, his visits. He didn't mind that Loki would never say it, he was just glad his brother welcomed the sight of him now. "Good day brother."

"Thor." Loki said simply, from his seat on the bed.

Thor moved to sit beside him. "I have something important to tell you today."

"Oh? And what would that be?"

"I want to tell you that I remember when father brought you home, and how things developed between us in the beginning."

Loki snorted. "Let me guess. You loved me instantly, I loved you instantly, and we were a happy family."

"Actually no. I did not like you in the slightest at first." Thor replied.

Loki's eyes shot to him in surprise. "What?"

Thor smiled. "Will you listen if I tell you the rest?"

Loki paused, before nodding.

"When father brought you home, he called mother to see him, and then called for me a while afterward…"

Thor burst into his parent's chambers, excited to see his father after he had been gone to war so long. He found his parents standing together by what he recognized as his old cradle, with his mother holding a bundle of something in her arms, and he was also shocked at the sight of his father with a patch over one of his eyes.

"Thor, come here my son." His mother said brightly.

Thor walked over, and stood in front of his parents, gazing curiously at the bundle. Was it a present? Why was it moving?

Frigga knelt before Thor, and revealed what was in the collection of blankets.

It had a chubby face, with pink cheeks, bright green eyes, and a tuft of black hair atop its head. When it saw Thor, it lifted a little arm out of the blankets and reached for him, gurgling softly.

Thor ignored it. "I don't understand."

"This is Loki, Thor. Your brother."

"He doesn't look like any of us." Thor observed.

"Not all siblings look alike my darling one." Frigga responded. "Look, he wants to shake your hand. Why don't you oblige him?"

"I don't want a brother." Thor said, still ignoring the hand the baby was reaching out to him with.

Odin and Frigga exchanged a concerned glance as Frigga straightened up.

"I am sure you will come to love him in time Thor." His mother said, looking at her husband for help.

"He will need you son. He will need someone to protect him, to guide him, to be his role model. Does that not sound like an honorable task?" Odin said, using his knowledge of Thor's desire for honor to try to get the boy to accept Loki.

Thor shook his head. "I want to play with Fandral and Volstagg. May I go now?" He asked, wanting to get away from the little one.

His parents exchanged looks again, before Odin nodded. "Yes, you may Thor."

Thor darted from the room without another word.

Frigga stepped closer to her husband, staring lovingly and sadly down at the small child in her arms. "He will need Thor. I had thought Thor would delight in having a brother."

"He will come around." Odin replied, and gave a rare smile. "This is an unusual child, he has already captured the heart of his new mother. It will not be long before the same happens to Thor."

"And what of the heart of his new father?" Frigga asked.

Odin held out his arms, and Frigga gently placed Loki into them. "He has already managed to work his way into the heart of his father as well."

Frigga absolutely beamed.

Five months later….

Thor didn't like that he was forced to share his nursery and toys with the little intruder. He didn't like that he stole his mother and father's attention from him. He especially didn't like his mother's talk of him sharing a room with it when the boy when he was old enough. He avoided having to interact with the child as much as possible. He wasn't cruel to him, said no unkind words, he figured Loki wouldn't understand anyway.

This behavior saddened Frigga, especially since it continued so long, and her insistence that the boys be together in the nursery was largely an attempt to try to close the rift between them. But it had not yet worked.

Today was another day that the two had been forced to stay in the room containing their toys together, with an old nurse watching them, while Frigga attended to her duties as queen and could not tend to them.

Thor sat as far away from Loki as possible as Loki played with some of Thor's old baby toys, quiet like he usually was. That was one thing liked about the baby, he hardly ever cried or made a lot of noise.

After an hour or so, he heard the nurse snoring, which was not surprising, this nurse often slept when she was supposed to be watching the children. Thor didn't mind, he felt more grown up if he was taking care of himself.

But then he heard Loki give a shriek, a noise Thor had noticed the child gave when he was exploring, and he couldn't help but look over his shoulder, and felt an unexpected stab of terror when he couldn't see Loki.

Thor leapt to his feet, looking frantically around the room, but he still saw no sign of the baby, and then felt his terror increase when he noticed the doors leading out to the balcony were standing open. In his forced concentration to ignore Loki and focus on his toys, he must not have noticed the nurse open them. He heard the shriek again.

Loki was on the balcony. And they were hundreds of feet up from the ground below.

Without thinking, Thor dashed to the balcony and found Loki trying to fit through a space between two of the short pillars that surrounded the edge of the balcony, and darted forward, grabbing the baby, easily picked him up, moving quickly back inside the room, kicking the doors closed behind him.

After a moment, he realized what he had done, and snapped his head to look at Loki, who he found was not crying as he thought he might be, but looking up at Thor with green eyes filled with… adoration?

Why had Thor been so concerned? Why had he been so quick to save the little one when he had hated him so much?

Thor pondered this and came up with only one answer. He didn't hate Loki. In fact, without him realizing it, he had actually become somewhat fond of him, in spite of his attempts not to like him. He had formed an instinctual need to protect his brother. He had been so focused on the jealousy he felt over loosing attention and having to share that he'd ignored it.

Brother.

Thor suddenly found he did like the idea. Someone to play with. Someone to take care of. Someone to protect.

Loki gave a giggle and reached up to touch Thor's cheek.

"That was dangerous Loki." Thor said, knowing full well Loki wouldn't understand. "I suppose you will get yourself into more trouble as you get older, and I promise I will protect you brother. I will always protect you."

"Tor!" Loki exclaimed.

Thor smiled. He really didn't know if that was actually Loki's first word, but he found himself hoping it was, and glad that his brother knew his name in spite of the way Thor had treated him.

When Frigga came to collect her sons to get them ready for bed, she was pleased and shocked to see Thor sitting on the floor, with Loki on his lap, reading to him, and Loki was falling asleep with his head cradled against Thor's shoulder.

Thor, without getting up, told his mother what had happened.

Frigga was furious, but decided to save her harsh words until later, not wanting to upset Loki with angry voices. The nurse would later be banished by Odin, who would also be furious when he learned of the fate that had almost befallen his youngest son.

Frigga took Loki gently from Thor. "Come along son, it is time for bed." They went first to her and Odin's chambers, and she laid Loki, who had not yet fully fallen asleep, into the cradle. "Now it's your turn Thor."

But Thor shook his head. "I want to stay here with him until he falls asleep. Please mother?"

Frigga let a smile touch her lips. There was at least one good thing that had come out of this incident. "All right Thor."

Much, much later in the night when Odin came to his chambers to see his wife, he was confused to see Thor asleep with his head on Frigga's lap, and that Loki's cradle had been moved closer to the bed where they sat.

"Thor wanted to watch his brother until he fell asleep. I'm afraid he fell asleep himself during that time." Frigga told Odin in response to the question look he gave her.

Odin felt his heart warm. "He has finally accepted Loki?"

"Completely." Frigga replied, looking tenderly between the two princes. "I am so happy. They will always have each other, even if they have no one else."

Thor watched Loki's face carefully after the tale was finished, but Loki maintained his carefully controlled expression.

"You… actually didn't like me?"

"I was a spoiled child. Suddenly not being the center of attention was unnerving to me. Nothing could have been better for me at that point than to have that happen really."

"But you were still the favorite. You went right back to being the center of attention after I could take care of myself." Loki snapped bitterly.

Thor sighed. "Did you not hear me describe how furious father was with that nurse? He and mother loved you almost immediately after you became part of our family, which was more than I did."

Loki merely glared at him.

"I will not have this argument right now. Mother and father were not the point of what I told you."

"Then what was the point?" Loki asked, irritated.

"To tell you I had an instinct to protect you, even when I thought I did not like you. Beneath the jealousy, I always did love you. Is that not a feeling you know?" Thor replied.

Loki looked at the floor. "I suppose it is." He whispered so quietly that he wondered if Thor had even heard him.

"That instinct, that love, has never, and will never die. I failed to protect you, despite my promise to do so. I am sorry for that. I renew my promise now that I will protect you from anything and everything. This time I will not break that promise." Thor put an arm around his brother, and pulled him close to his side, and Loki just let him. "Whether you like it or not." He added with a slight laugh.

Loki did not laugh, but, feeling something within him break, he turned slightly, putting his arms loosely around Thor's neck and burying his face in Thor's shoulder, if anything so he wouldn't see Loki's face. "You know, as long as I can remember, I've always felt safe when you were there, somehow even when things were falling apart between us." He couldn't believe he was admitting this, but somehow the words were slipping out faster than he could even attempt to stop them.

"I will not break that promise again." Thor repeated, circling his other arm around Loki.

Loki sighed as Thor ran his hand through Loki's hair.

Safe. Everything about this embrace, about Thor's words, about his promise screamed safe. Screamed that nothing could hurt him. That the instinctual love and protectiveness Thor had spoken of was still there.

And Loki's heart also heart was screaming at him that the love and protectiveness went both ways. That it existed in Loki's heart towards his older brother too. And, for the first time in a long time, Loki listened to his heart.

End

A/N: Most stories about Thor and baby Loki have Thor loving Loki right away. However, it's often the case that older siblings don't like their younger siblings at first, because of the attention issue I went over.

My parents tell me this was the case with me when my sister was born, but I don't remember it at all. Either way, eighteen years later, she's my best friend, and we're extremely protective of each other.