Percabeth can't get a full nights rest without each other

Leo will stay up for days and lose track of time while working on a project. Calypso and Piper are the only people able to get him to stop living off of coffee

Nico dreams about what could have gone differently if he had snuck his way onto the quest with Bianca instead of Percy

Will crys for days if he loses a patient, he asks Nico to let him talk to them so he can apologize. There hasn't been a single patient who has been mad with Will, instead they apologize to Will for causing him so much grief and tell him to move on and do his best in the future

Hazel sees Percy as an older brother and will shadow travel to Sally's whenever she has a nightmare cause she doesn't want to worry Frank. Percy, Annabeth, and Hazel will be found snuggling on the couch the next morning

Frank will turn into random animals and preform silly dances if he ever finds any of the Argo 2 crew sad

After the events of The Burning Maze Piper and Calypso will be found with Calypso fiddling with the microwave, toaster, or anything electronic and Piper laughing histerically whenever Calipso's scared by something

With Reyna's sister being an Amazon Thalia has made Reyna an honerary member of The Hunt and invites Reyna with them whenever they're looking for a difficult to find monster

Carter and Sadie have nightmares of what happened during the 5 demon days (It's been a while since I've read the Kane Chronicles)

I'll probably do another part to this once I get more ideas