In her Shoes: Jennifer Weiner

This was a heartfelt book about the bond between sisters. Rose and Maggie lost their mother when they were 8 and 6. Since then Rose has been taking care of selfish Maggie with varying degrees of effectiveness. Rose finally gets a boyfriend and is awoken in the middle of the night by a man telling her she needs to pick up a drunken Maggie. Maggie has lost her apartment and her father and stepmother won't take her in since she is a thief and nothing but trouble. After Maggie sleeps with Rose's boyfriend she disappears and one day sends Rose a note that she is living with a long lost grandmother. The family comes back together and Rose ends up marrying someone worthy of her.