According to People, Bernthal popped the question with a ring featuring five diamonds to represent their combined five children, after a hike and picnic in New Mexico on Saturday.
Bernthal is a 46-year-old father of three who is the CEO at his consulting agency, Kelton Global. Before founding the company, the Washington, D.C., native worked in the Clinton White House and earned an Emmy award working as a producer at NBC News.
Sandberg, a Harvard Business School graduate, was previously married to Dave Goldberg, who died in 2015 from severe head trauma and blood loss after falling off a treadmill while the couple were on vacation in Mexico. They had two children together.