I'll be there for you

Amber and Marcus have been living together since Amber was a baby. Her real mom was killed by vampires and Marcus and his parents took her in. Amber is happy living with them but She wishes Marcus would be a little nicer to her. She doesn't understand why he's this way because they use to be good friends and close to each other. What will happen went Marcus' parents are killed and him and Amber have no way to go? Will they get along again? Marcus is 18 and Amber is 16 now.