Chrissy Teigen and John Legend's band is growing once again.

Five months after the Cravings author gave birth to daughter Esti, she and the "All of Me" singer have welcomed a baby boy via surrogate, a son named Wren Alexander Stephens.

In addition to Esti, the bundle of joy—born June 19—joins the couple's kids Luna, 7, and Miles, 5, in the Stephens squad.

"For as long as I can remember, I've always wanted four children," Chrissy wrote on Instagram June 28 while announcing Wren's arrival. "As a little girl, 2 glow worms and 2 cabbage patch dolls were perpetually in my arms, helping me stir in my kitchen, watching Alf with me. We'd sleep together nightly, each getting the same amount of kisses as to not make the others jealous."

"My mom always searched for the Pound Puppy with 4 pups in her pouch, having no qualms about opening and peeking inside before purchasing," she continued, before referencing her and John's late son, Jack, who passed away in 2020 when she suffered a pregnancy loss. "After losing Jack, I didn't think I'd be able to carry any more babies on my own. 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."

Chrissy went on to explain that she and John reached out to a surrogacy agency in 2021. "With our first correspondence inquiring about perhaps having 2 tandem surrogates," she noted, "to each bring us a healthy baby boy or girl. Twins, kinda?!"

Early in their surrogacy journey, Chrissy shared, she told John that she wanted to "try to carry just one more time" and they restarted IVF.

"We made new embryos," she wrote. "We did my transfer, and were so happy to learn it worked—we were pregnant with our little girl, Esti."

As Chrissy mentioned, it was around this time that they found a "compassionate surrogate" named Alexandra. 

After the first embryo they tried with Alex didn't survive, they took a pause before trying again. And as Chrissy revealed, "As we crept toward the safe zone of my own pregnancy, we were overjoyed to learn Alexandra had become pregnant with a little boy. Our little boy."

"We ate hot pot to celebrate, watched Vanderpump Rules with our growing bellies, our families blending into one for the past year," the 37-year-old continued. "Just minutes before midnight on June 19th, I got to witness the most beautiful woman, my friend, our surrogate, give birth amidst a bit of chaos, but with strength and pure joy and love."

Chrissy then thanked Alexandra for the "incredible gift" of Wren, noting that his middle name, Alexander, is in honor of her.

"Our hearts, and our home, are officially full," the Chrissy's Court star concluded. "And to our Jack, we know both their angel kisses are from you."

John also shared the family update on his Instagram June 29, posting a series of photos with their baby boy. "Wren Alexander Stephens," he wrote, "our new love."

It was just months ago, in February, that the EGOT winner shared how kids Luna and Miles were adjusting to life with their baby sister Esti.

"We weren't sure how they would take it," he exclusively told E! News correspondent Courtney Lopez at the time. "I felt like they were a little jealous when mommy was pregnant."

"But as soon as Esti arrived," he continued, "they're just exploding with love and joy, and they're so caring and loving toward her. They want to hold her, they want to kiss her and it's really exciting."

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