Aaron Carter appears to be on the mend. The 29-year-old former child singer and younger brother of the Backstreet Boys' Nick Carter posted on his Instagram page Saturday morning before-and-after selfies of himself posing shirtless and showcasing what he says is a 30-pound weight gain. Aaron recently underwent personal and legal turmoil and spent time in a treatment facility. He has also spoken in the past about having an eating disorder.