What do u do when theres a 14 yr old on ur doorstep?

ok so me and my sis are staying at my aunts house. my sis friend, a 14 yr old boy named jesus, lives in the same apart. complex and has been hanging out with us since about 5:30. when he tried to go home around 9 his uncle locked him out for no reason and told him to go away. so he came back and would try to get back in every 30 mins or so. this last time his uncle said that he needs to go away or he was gonna call the cops. it is now 1:44 in the morning and my aunt made him come in the house because she didnt want him staying outside this time of night. he's only 14 yrs old and has nowhere else to go. his parents are in puerto rico his dad in prison and his mom is brain dead from a car accident so he has no one to call or go to. we dont want to call the cops cuz we dont want to make the situation worse for him when his uncle decides to let him in and punish him in other ways. what should we do. if the cops are called will my aunt get charged with kidnapping? any advice?