A source close to the couple tells PEOPLE Bezos’ wife of 25 years, MacKenzie Bezos, and Sanchez’s husband, Hollywood agent Patrick Whitesell, were aware of their relationship for a while.
“Their families dealt with this in the fall,” says the source.
The 55-year-old Amazon CEO and the news anchor, 49, struck up a working relationship while collaborating on several projects together and “gradually” fell for each other, adds the source.
Despite the headlines about their romance, Sanchez and Bezos — whose estimated $137 billion net worth makes him the world’s richest man — have shown no signs of slowing down.
“The world is catching up to it, but it has had zero impact on their relationship,” says the source close to them. “They’ve never been stronger.”
For more on Jeff Bezos and his divorce pick up the latest issue of PEOPLE on newsstands Friday
Last week, Bezos and his wife announced they were separating in a joint statement he shared on Twitter.
“We feel incredibly lucky to have found each other and deeply grateful for every one of the years we have been married to each other,” they said in the statement.
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The exes have four children: three sons and a daughter. Sanchez is also divorcing her husband, Hollywood agent Patrick Whitesell, after 13 years of marriage, PEOPLE confirmed. They have two children together. She also has a son from a previous relationship.
A source previously told PEOPLE that Sanchez has a “bubbly” and “social” personality.
“Lauren has a really bubbly personality and likes to have fun and go out,” a source explains of the former news anchor turned helicopter pilot. “She’s very social — always has been and always will be. She’s the kind of person who at 49 will still grab a group of girlfriends and helicopter to the desert for a weekend at Coachella.”