Paris Hilton is proving to be a stand-in mother for new boyfriend Cy Waits' seven-year-old daughter Shea, Breaking Celebrity News has learned exclusively.

It's a sudden change of pace for the hard partying hotel heiress, who was arrested in Las Vegas in August with cocaine in her purse.

"Cy is a dad and he is combining his part time parenting duties with his fledgling romance with Paris," said a source close to the couple.

While Paris is not yet officially a 'step-mom', she has made no secret, in the past, about wanting to become a mommy dearest.

"It's been my dream to have four babies by 30," the heiress, 29, said a few years ago.

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