Before welcoming their third child, John Legend and Chrissy Teigen experienced a sad miscarriage, which they have been quite open about.

The couple has now disclosed how they secretly welcomed a fourth kid via a different method.

Scroll down to find out more about the announcement of their son’s birth on Wednesday.

The couple received assistance from a surrogate called Alexandra, and as a way to thank her for helping them welcome their child into the world, they did something extraordinary.

Chrissy stated in a blog post that Alexandra is “the most incredible, loving, compassionate surrogate we could ever imagine.”

“I knew she was a perfect match for us the moment we spoke to her. All our wishes and dreams aligned,” Chrissy wrote. “I wanted to be her friend, I wanted our children to play, I wanted dinner together, I wanted to lay my head on her belly and be able to feel the hiccups and kicks. I wanted them to be in our lives for as long as time would allow.”

She described how Alexandra “fought to get ready for a second transfer,” giving up “her own body” for operations and experiencing “the mental toll” that went along with it.