Chrissy Teigen, John Legend welcome baby No. 4 via surrogate

Chrissy Teigen and John Legend are now a family of six.

In a moving Instagram post Wednesday, Teigen revealed that she and Legend recently welcomed their fourth child together, a baby boy named Wren Alexander Stephens, via a surrogate.

"Our hearts, and our home, are officially full," she said in the post, which included photos of Wren nuzzling against her chest and moments she shared with her surrogate, Alexandra.

The model and "Cravings" cookbook author, who gave birth to her daughter Esti in January, shared how she met Alexandra early in her surrogacy journey, which was shortly after she suffered a miscarriage in 2020.

"After losing Jack, I didn't think I'd be able to carry any more babies on my own," Teigen said. "To be honest, I've personally blocked out a lot of my mindset during that time, but one clear memory is being surrounded by people who wanted to make sure I wouldn't go through that pain and loss again."

"In 2021, we reached out to a surrogacy agency, with our first correspondence inquiring about perhaps having 2 tandem surrogates, to each bring us a healthy baby boy or girl," she continued. "Twins, kinda?!"

"At some point in our surrogacy journey, I came out of a therapy session, walked downstairs and said to John -- I want to try to carry just one more time. If it doesn't work, we will be okay. We've already seen the worst," she said. "I remember saying I just couldn't go on wondering my whole life if I should have tried again."

Teigen went on to say that she restarted the IVF process, and during that time she and Legend met Alexandra, saying "she was a perfect match for us the moment we spoke to her."

"All our wishes and dreams aligned," she said. "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."

During their surrogacy journey, Teigen shared some of the challenges that arose as well. In her post, Teigen explained that the first embryo in that process didn't survive.

"How much she gave up of her own body -- surgeries to get scar tissue cleared, the mental toll it takes to go through all of that for yourself, much less for people," Teigen said. "Not wanting to rush the process, we took a breath and... were just patient."

After a second transfer, Teigen, who was pregnant with Esti, said that she and Alexandra experienced pregnancy together. Wren was born "minutes before midnight on June 19."

"We want to say thank you for this incredible gift you have given us, Alexandra," Teigen said in her post. "And we are so happy to tell the world he is here, with a name forever connected to you, Wren Alexander Stephens."

Teigen ended her post with a sweet tribute to Jack, saying, "We know both their angel kisses are from you."

Legend also took to Instagram to share a sweet photo of him with Wren, Esti and the couple's eldest children, Luna, 7, and Miles, 5.

"Wren Alexander Stephens, our new love," he captioned the post.

Teigen and Legend tied the knot in 2013. Their daughter Luna was born in 2016 and Miles was born in 2018. Like Esti, both children were conceived through IVF.

In 2021, Teigen opened up about her struggle with infertility in an interview with Refinery29 and said "there's no one way to [become a parent]."

"There's no straight road at all," she said. "I've seen the highest of highs and the lowest of lows with it. I encourage anyone to be open and honest as they'd like to be."