The news comes as a complete surprise, as the couple kept both the pregnancy and birth under wraps. It was actually Bledel's Gilmore Girls co-star, Scott Patterson, who spilled the beans!
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Surprise! 'Gilmore Girls' star Alexis Bledel is a mom
Alexis Bledel and Lauren Graham of 'Gilmore Girls' (Photo by M. Caulfield/WireImage for The WB Television Network)
NEW YORK, NY - MARCH 27: Kelly Bishop and Alexis Bledel (who co-starred on 'The Gilmore Girls') attend 'Regrets' Off-Broadway opening night celebration at Beacon on March 27, 2012 in New York City. (Photo by Bruce Glikas/FilmMagic)
NEW YORK - JUNE 26: Actress Alexis Bledel attends the Veuve Clicquot Polo Classic at Governor's Island on June 26, 2010 in New York City.
Gilmore Girls cast members, left, Yanic Truesdale, Lauren Graham, Kelly Bishop, Alexis Bledel, Keiko Agena and Scott Patterson at the 17th Annual TCA Awards held at the Ritz-Carlton Hotel in Huntington, CA., Saturday, July 21, 2001. (photo by Kevin Winter/Getty Images)
370100 07: The cast from Warner Bros. TV series 'The Gilmore Girls.' (Photo by Warner Bros./Delivered by Online USA)
370100 08: Alexis Bledel and Lauren Graham star in Warner Bros. TV series 'The Gilmore Girls.' (Photo by Warner Bros./Delivered by Online USA)
370100 09: Alexis Bledel and Lauren Graham star in Warner Bros. TV series 'The Gilmore Girls.' (Photo by Warner Bros./Delivered by Online USA)
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"It was great to see [Alexis]. She's really blossomed as a woman and now she's a proud new mother and married and happy," Patterson dished to Glamour magazine during an interview promoting the show's highly anticipated Netflix reboot. "I remember her as an 18-year-old kid, fresh out of college coming into Hollywood and being a little overwhelmed. She's just the most likeable, intelligent person and adorable human being. She hasn't changed at all. She looks the same."
"We're comparing notes because my son is about a year and a half older than her young son," Patterson -- who welcomed his son, Nick, in July 2014 -- continued. "I'm showing her photos and videos and what to expect. We're just really enjoying each other's company."
Bledel, 34, and Kartheiser, 37, are no strangers to surprises, however. The two tied the knot in 2014 in a top-secret ceremony in California.