Judge enters not guilty plea for dead tot's mother

CLAYTON, Mo. (AP) -- A St. Louis County judge has entered a not guilty plea on behalf of Shelby Dasher, the young mother accused of killing her 13-month-old son because he wouldn't stop crying.

The 20-year-old Dasher made a brief court appearance Thursday during which the judge also assigned the public defender's office to represent her.

Dasher was charged with second-degree murder on Wednesday, a day after she reported that her son, Tyler, was missing from his crib. The boy's body was found a few hours later in a field near the home in Affton where he lived with his mother and grandmother.

Prosecutors say Dasher confessed to striking the boy out of frustration.