The actors have kept their relationship discreet since meeting on the set of Mad Men in 2012
The actress’ rep confirmed to PEOPLE that the new addition arrived last fall after her Gilmore Girls revival costar Scott Patterson revealed Bledel’s mom status in Glamour.
“She’s really blossomed as a woman and now she’s a proud new mother and married and happy,” Patterson said. “We’re comparing notes because my son [born July 2014] is about a year and a half older than her young son. I’m showing her photos and videos and what to expect. We’re just really enjoying each other’s company.”
As with their courtship and subsequent marriage, the private pair had kept news of their growing family under wraps.
“It’s something I realized about the most important things in my life,” Kartheiser told Vulture in 2014 about keeping his lips sealed when it comes to his personal life. “If I share them with the world and I open that door to their fuming anger that they need to get out or their adoration that they want to flaunt, it lessens it. It cheapens it; it weakens it. And it’s magical, love, and all of that is profoundly spiritual, and it just doesn’t feel right.”
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The couple met when Bledel guest starred as the mistress of Pete Campbell (Kartheiser’s character) on season 5 of Mad Men. Kartheiser insisted to New York Magazine that he kept it “completely professional” and didn’t become romantically involved with Bledel until two months after the season wrapped, but costar Jon Hamm said he sensed a connection between the future-spouses long before they made it official.
“I did know he liked her from a very early point,” said Hamm. “I was a supporter of that union.”
Even show creator Matthew Weiner could feel the love in the air. “I told Vinny that they would be great together. I was like, ‘Don’t blow it!’ ” he told New York Magazine.
“Honestly, they’re a really good match,” he added. “They’re both very down-to-earth, with a sense of responsibility and strong family ties. And they’ve been acting since before they can remember, which makes for a very special personality. It’s not just that I thought they would look cute together.”
Bledel and Kartheiser finally went public with their relationship at an October 2012 press event. Then in March 2013, Kartheiser shyly admitted to OTRC.com that he was engaged. “Yes, I don’t know, yes,” he replied when asked if he was getting married.
“It was purely comedic but he was giving [Elisabeth] and I a facetious rendition of his planned proposal,” Paré said at the season 6 premiere of the show. “We were like, ‘Great! Lets do this one without cursing and without yelling!'”
“They are such a yin and yang,” Moss added about the couple. “I’ve known Vinny for 12 years and Alexis is just the sweetest. I’ve never seen Vincent like this. It is really cool.”
The next month, Bledel gave the world a glimpse of her gorgeous octagonal-shaped diamond engagement ring at the premiere of Remembering Sunday.
The twosome tied the knot – secretly, of course – in a June 2014 ceremony in California.
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Although officially husband and wife, Bledel and Kartheiser didn’t make a public appearance together until the January 2016 Screen Actors Guild Awards.
The reclusive life is nothing new for Kartheiser, who told Vulture in 2014 that he tends not to leave his house because, as he put it, “there’s nothing out there.”
Although he prefers to stay a healthy distance away from the grid, Kartheiser admitted to New York Magazine that his lifestyle isn’t quite as eccentric as he led reporters to believe in his pre-Bledel days. “Like, I don’t have a toilet at the moment. My house is just a wooden box. I mean I am planning to get a toilet at some point. But for now I have to go to the neighbors. I threw it all out,” he told The Observer in 2010. Kartheiser later clarified that he has never lived without a toilet, but he does maintain that he lived without a car in L.A. for years, commuting to the Mad Men set on public transportation.
“I go on the bus, I walk,” he told The Observer. “A friend left his car recently at my house and I took it out one day just for 15 minutes and it was terrible. You know why? I felt like I was back in L.A. again. Four or five years ago, when I had a car and I had been out of the city, I wouldn’t feel I was back until I got in the car, you know. But now I feel off the grid. I feel that I am not part of the culture. And because I don’t have a car I don’t really go anywhere to buy things.”
But by 2014, Kratheiser’s lady love was already encouraging him to tune down his quirks. “I still dress like I did in high school. My fiancée bought me all of this,” he told New York Magazine about his dapper outfit. “She’s like, ‘Honestly, another ripped T-shirt? Put this on.'”
Now parents, the couple remain comfortable in their private ways, but Kartheiser has seemed to move on from his living in “a wooden box” phase, and we even got a rare peek of their marital style when their chic Brooklyn Heights penthouse duplex recently went on the market.