Lauren Azie, 23, allegedly stole cash and jewelry while babysitting for the family between October 24 and November 18.
Officers arrested Azie on Wednesday.
She is charged with fourth-degree grand larceny.
Azie was also arrested in early December after police say she stole laptop computers, jewelry and other valuables from another Plainview home while cat sitting.
In that case, she had been working for the animal owner for about 10 days when she staged a burglary at the home on Northern Parkway on Nov. 2, police said.
She allegedly sold some of the jewelry at a pawnshop in Hicksville the next day.
Detectives ask anyone who may have information regarding this case or similar cases to contact Crime Stoppers at 1-800-244-TIPS. All callers will remain anonymous.