Kayla is revealing a part of her dating past which unfolded before Teen Mom: Young and Pregnant began. And now, years later, a former boyfriend is back in the MTV mom's life.

"Ryan is my ex that I dated in high school when me and Stephan were broken up," Kayla explains in the sneak peek above from tonight's episode. "We had only dated for a few months. When I was pregnant with Izaiah, he reached out to me asking if it was his baby, and I had told him no."

But Ryan still wants to find out once and for all if the three-year-old is actually his son. Does Kayla now think he might be the father of her firstborn? Or does her previous belief about Izaiah's paternity remain the same? Watch the clip, and catch Teen Mom: Young and Pregnant tonight at 9/8c.