She's an Orphan. A very brave kind hearted kid that a little unfortunate. Her dad left with her 2 siblings when she was very young (4-5 y/o). Her mom got sick and past away soon after her dad left. 

Currently adopted by a wealthy family but they don't treat her that well. She knew that it's unhealthy but after living alone for so long.They're all that she have. 

 She met Ace because her dad got some business at Ducklair tower. Ace find her to be a very polite person even for a kid. They got a long very quickly but Amber afraid that if she keeps talking, she'll get too attached and she might never see him again so she tried to end the conversation but couldn't since it was sooo fun. She never got a chance to talk to other kids this much. They became close and Ace would come visit her a lot.