A Prince for a Prince. (джен)

Please note that this is Unbeta'd and Very Rough.
For Avengers Assemble Prompt:
Laufey survived. Since he was injured and Jotunheim was partially destroyed, there was no war. However, he somehow discovered that Odin found and raised his son as his own. Deciding to reclaim what's his, Laufey hatches a plan to kidnap his son. It goes off with only one hitch: He thinks Thor's his son, since Odin had banished him, clearly displaying less care than for Loki.
Ever since the Battle of N.Y, Loki's been in prison. However, Odin decides to make a trade with Laufey. Loki for Thor. Laufey agrees to this and they make the trade. However, Loki does not want to be with his biological father and Laufey, while he wants Loki, doesn't actually care about him (he did abandon him, after all). He just doesn't want the All-Father to have him. So, Loki's kept locked up and hurt when he disobeys Laufey's commands.
When Thor comes to and finds out what happened, he disobeys the All-Father's commands and goes to rescue his brother. By the time Thor gets there, Loki's given up all pretense of not being Thor's brother. He just wants his big brother to save him from his biological family.
Please no Thorki.