Brandon Jenner and Girlfriend Cayley Stoker Expecting Twin

The 38-year-old artist and his girlfriend, Cayley Stoker, exclusively tell PEOPLE they are having twins early next year.

“We are at 12 weeks now, so near the end of the first trimester,” Jenner tells PEOPLE. “We’re madly in love and excited!”

Stoker's pregnancy was announced to Jenner's 3-year-old daughter Eva James, whom he shares with ex-wife Leah.

“We told her together,” Jenner says. Leah, Cayley, and I sat down with her and informed her what was going; she was excited and happy. She's thrilled to be a big sister.”

The couple is enthusiastically preparing for their twins, and their families are thrilled!

“Our families love it. Jenner thinks it's great news.

“We have decided not to find out,” Stoker explains. No one wants to know. Be prepared to be surprised.”

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