My Sister's Keeper — Edna Curry

Mystery novelist Candi finds herself in trouble way over her head when her sister, Jolene, drops off her baby asking Candi to keep it safe from its father and disappears. She needs to meet her deadline and doesn't have time to bail Jolene out of trouble for the umpteenth time. She's sick of responsibility. But FBI agent Luke shows up, saying Jolene is part of a jewelry thief gang. Worse, Luke suspects Candi of being one of the thieves herself. Assigned to watch her, he finds himself falling for her and the cute baby, wanting her, but never gets involved with a suspect. Then they find that secrets from the past threaten Candi's whole family.