The molestation was a retcon that turned an already ugly situation into something even uglier.
Vandal Savage killed Mary Pratt after she gave birth and kidnapped their newborn son (Grant, of course). Everyone was led to believe that she died in childbirth, and the baby was stillborn. Vandal gave the kid to a family of evil scientists to use as a guinea pig. They froze him and unthawed him a few decades later, and gave him to lackeys to raise. The lackeys allowed Grant to be experimented on under the cover of normal childhood operations (tonsil extraction, etc.), and they turned on Grant when his powers finally manifested at age 16. Neither "parent" really loved him, but the mother at least made an effort of acting as if she did. The molestation retcon happened in Devin Grayson's Titans series.