Every. Single. Headcanon.

                                    

                                          
(I NEEDED TO HAVE ALL OF MY HEADCANONS IN ONE PLACE SO HERE IT IS)
(this will also get frequent updates so-)
I imagine both of them are only childish around kids but they act older around themselves and peers
(Trauma)
Moon has separations anxiety because when sun wasn't around and it was just him and star  the people would lock him in a storage room by himself for weeks. Now he doesn't go into storage rooms. 
Sun is afraid of the dark and was afraid of moon at first but that changed when moon started to comfort them about the dark. 
(Relationships with peers)
Sun actually has a good relationship with the glam rocks but is a little weary about the staff bots. He hates the workers for what they did to moon years ago, but acts nice towards them, but sometimes leaves passive aggressive remarks.
Moon is also friends with the glam rocks, in fact, he was the one who introduced sun to them. Moon sometimes destroys the staff bots for fun, but sun tells him not to. Moon is terrified of humans besides Vanessa, and y/n, (yes ik I put y/n in this) but acts calm if he needs repairs, but he won't go without sun. 
(Music preference)
I feel like sun would like heavy metal or something chaotic like that but moon hates it because it's loud and "obnoxious"
(I'm not saying sun is a EmO BaDbOy I'm just saying he likes it because it's chaotic and so is he-) 
Moon prefers more calming music, and also he loves the song orphan tears because yes-
(Children) 
Sun hates children, because he dosent have the patience to deal with him and he has severe anxiety. 
On the other hand moon is great with kids. He loves singing them to sleep and even playing with them
(More updates coming soon)