Maria Ridulph was 7 years old at the time of her death.  On a cold, dark night in 1957, she was outside playing with her best friend, when a stranger approached (remember, back in 1957, kids playing outside was the norm... and for the most part, safe.)  The young man began talking to them and asked if they wanted to play.  Maria ran home to get a doll, and her friend ran home to get her mittens.  When her friend returned, Maria and the young man were gone, and no one ever saw Maria alive again.  Though it took many years, her killer, an ex cop, was finally caught and convicted.  Here's her story:

http://news.yahoo.com/ex-cop-convicted-1957-murder-ill-girl-7-163107371.html