Jessica Simpson says that she and Eric Johnson are probably done having children; plus, find out about Maxwell and cousin Jagger's playdate! Credit: Jamie McCarthy/Getty Images for Jessica Simpson Collection

Simpson wants to stop! Jessica Simpson revealed that she and her husband, Eric Johnson, probably won't be welcoming baby No. 3 into the family anytime soon — if ever.

"No more kids on the horizon," the singer and fashion mogul, 35, told Entertainment Tonight at the 10th anniversary of her clothing company in NYC on Wednesday, Sept. 9. "That would freak me out a little bit."

Simpson and the former NFL hunk, 35 — who married in July 2014 — are the proud parents of daughter Maxwell, 3, and son Ace, 2. When not juggling her children or focusing on her fashion empire, Simpson also likes to spend time with her extended family. She recently entertained her newborn niece Jagger, 1 month, whom sister Ashlee Simpson and Evan Ross welcomed in July. (Ashlee, 30, also shares son Bronx, 6, with ex-husband Pete Wentz.)

"Jagger just came over to see me, Maxwell, and Ace the other day, and she's so tiny and so sweet!" Jessica gushed to ET. "And Maxwell is just obsessed! She has baby dolls, she wants to be a mom already. She's a caretaker!"

Running after everyone has proved to be good exercise, too. "A lot of squats! A lot of push-ups, got to keep these things up," she said of her workout regimen. "And running around with my kids. That is a diet in itself."

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