Can me and my boyfriend take custody of his sisters baby?

my boyfriends sister had her baby last Wednesday and everything was doing good and today me and my boyfriend got a phone call from his sister and she was crying and said that her baby got taken away by the state. she has 2 other kids that got taken away because her boyfriend the baby daddy was abusing her and always screaming at her and when she found out she was pregnant this time when she was 6 months pregnant she finally got SSI and she lived with me and my boyfriend till she got snuff money to get her own place and a month later she moved out and had a place of her own and she was doing fine and she had all the stuff for the baby and everything the baby had her own room and everything and last wednesday she had her baby and today her baby got taken away. so could me and my boyfriend get custody of the baby? please help me