A convicted murderer pleaded guilty Monday to molesting an 11-year-old girl while he was on parole in Joplin and was assessed a new 10-year prison term. Olen L. Robinson, 42, pleaded guilty to first-degree child molestation at a hearing in Jasper County Circuit Court in a plea agreement that dismissed a second count of child molestation that he was facing and capped the prison time he would receive at 10 years.