Child Killer Pauline Zile

Pauline Zile would go on television and tearfully plead for her 7-year-old daughter's safe return after she said she had been ad been abducted from a flea market. The truth was, her new husband had suffocated the girl. They would hide her body in the closet until deciding to bury her days later.
Why would Pauline cover for the girl's stepfather? Was she afraid of his temper or did she have some other motive?