It was one of those amazing Ásgard afternoons. The air was warm but not hot, and the breeze was cool but not gusty. Thialfi and Roskva were down by a creek, far away from the High Halls. Roskva would find a piece of wood on the ground. Thialfi would then take his knife and carve a little hole in it. Roskva would look for a little stick and a leaf. The little stick would be stuck into the hole, and the leaf propped up against it. This would then be placed carefully into a quiet pool of the stream in which they played.
Sometimes these little ships sailed proudly across the pool. More often, they just sort of flopped over onto their sides and drifted away. Whatever the result, another ship was soon in the works.
Recall the origin of these two children: their grandfather could give them so little, and they were hungry. When Thor and Loki happened upon them near their home at the edge of Midgard, Thor offered to share his dinner of goat meat. They accepted eagerly. While Thor said they could eat as much meat as they liked, he warned them not to break the bones of his goats. They agreed to this, but it was a promise that Thialfi did not keep. The marrow of that leg bone was just too tempting.
The next morning, when Thor used his magic over the pile of skin and bones to recreate the goats that pulled his cart, one of them was lame. As you might expect, Thor was very angry, because he knew what had happened. Thialfi immediately confessed, and said he deserved what was coming to him. Thor was so impressed with Thialfi's forthright honesty that his anger abated, and he offered to take the children into service at his home. The grandfather knew he would miss his only remaining family, but he also knew their life in Ásgard with Thor and Sif would be much better than anything they could hope to have with him.
So, how long had they been here now? It was hard to tell. Still, even with a steady diet of Idunna's apples of youth, the occasional new whisker broke through Thialfi's cheek.
They were happily watching one of their more successful creations cruising along in the water, when Thialfi said to his sister, "I want to go back to Midgard."
Roskva stopped. Her eyebrows went up a little. "We go to Midgard all the time, with Thor, on his adventures. Then we come home."
"Yes, I know, but I mean I want to really go back."
"Why would you want to do that? Grandfather is surely dead by now."
"Yes, I know. But I want to grow up."
"Whatever for?"
"Because I want to become a man."
Roskva stepped back and looked at her older brother. In the crook of her arm was what had once been a doll, made for her out of some scraps of cloth by their grandmother shortly before she died. Whenever Sif could get it away from Roskva, she had carefully washed and mended it, as had Frigga's handmaidens from time to time. In spite of all these efforts, only Roskva could now see and love this rag for what it once had been. She was still a little girl. But she had wisdom in her, far beyond her mere ten thousand years. She gave her brother that look little sisters give older brothers when the brothers are about to do something risky or rash. You know the one.
"You can't go back. Who would get you out of all that trouble you're always almost in?"
Thialfi didn't like what the question implied, but he was honest, and he knew it was true. "You could come with me."
"I don't want to go back to Midgard. Not like that. Not yet, anyway. I like it here with Thor and Sif."
He stood resolutely. "Then I will go by myself, and I will have a grand life as one of the best of men."
"How do you know that? Perhaps it will be grand. But what if your life turns out as most of our little boats have done here this afternoon?"
Thialfi didn't know what to say to this, and the boat building and sailing game was not so much fun after that. Sunna was going down, so they went quietly back to Bilskirnir for dinner.
After the meal was over, Thialfi announced his intentions and asked Thor's leave to go. The Thunderer and his wife looked at each other with that look parents give each other when they realize their young children are not so young anymore. This look is not quite happy and not quite sad, as they watch mortal time move on. It is that wistful look. You know the one.
Thor said, "What you ask, and what you wish for, is commendable. But remember that I will no longer be able to help you in the same way if things do not work out well. You will have to live by your own wits and strength, without the kind of magic we have here in Asgard. This is the life of men and women in Midgard. Is this what you want?"
Thialfi said that it was.
Sif stood and left the hall for a moment. Then she returned with a package, which she gave to Thialfi. "Thor and I knew this time would come, and we prepared for it long ago. Here are clothes, such as young men in Midgard wear. They are... different from what you have become accustomed to here. Put them on and see if you still wish your wish."