Non-league footballer Luke Foster had a son with Rebekah eight years ago before she dumped him for the Leicester City frontman, and the pair have been in a year-long feud over payments to help raise him.
According to The Mirror, the Child Support Agency has now ruled on the matter and ordered Foster - currently working behind the scenes at Oldham Athletic - to contribute £500 a month.
"Luke didn't pay maintenance for months and the CSA were chasing him," a source told the newspaper. "Becky just wants him to take some responsibility."
England international Vardy is thought to earn around £80,000 a week with the Foxes.