We'll Never Be Yours

Blaze is a normal 16 year old boy. He has a mom, a dad, a baby brother, and an older sister. Blaze's parent's take a two week trip right before school is out, and leave Cierra, Blaze's older sister in charge. After being gone months, Cierra becomes an unfit guardian. She spends all her time drinking, doing drugs, or sleeping around. Blaze can't handle it anymore, and runs to the only place he can think of- his therapist's house.
Blaze and his baby brother, Danger, are warmly welcome in the house over the summer.
School starts up again, and Cierra doesn't remember anything...including her family. But once she sees Blaze at school again, she remembers the call- their parent's are dead. Cierra wants Blaze and Danger back in her life, but Blaze refuses. Being eighteen though, she can legally claim custody of Danger. If she gets him, can she raise him properly?