It Wasn't Me by Andrea Yvette

Sara and Angela are identical twins growing up living in the Mississippi Delta. Sara, the younger and more crafty of the two, is always drumming up trouble. Problem is, with her medical condition, only her twin gets in trouble and Angela spends a lifetime covering the tracks and taking the fall for her sister's actions. When the unthinkable happens during their teenage years, Angela once again comes to the rescue and covers her sister's tracks the best way she could. For a great many years, nothing became of their crime and on they went into their successful adult lives. A random trip back to the Delta brought it all home when they were confronted with the very issue they'd thought was long buried. This time when the lies were blurted out to save her own behind, Angela didn't let her sister get away with pinning something of this magnitude on her...or did she?