The Twilight star, 36, reposted Gonzales' cute announcement video on Instagram Wednesday. Sporting a huge grin, Lutz beamed as Gonzales, 33, held their daughter Ashtyn Lilly, who turns 1 on Feb. 22, with one hand and used the other to pull the strings attached to a heart-shaped piñata.
Inside held blue and pink confetti that would reveal the sex of their second baby.
"The suspense is killing me with every pull!" Gonzales wrote on the clip. "Then I got to the one I knew would open it..."
Round pieces of pink confetti poured out, convincing Gonzales baby number two is a girl.
"So excited picturing Ashtyn having a little sissy," Gonzales added.
But as Lutz shook the piñata, blue pieces also poured out, leaving his wife confused.
"But wait — this is my husband. Nothing is as it seems...," she wrote on the video, asking, "Why is there pink AND blue? What the heck is going on???"
In the clip, she double-checked with Lutz that they aren't having twins, which he confirmed they are not.
He explained that there are different amounts of blue and pink coins inside the decorative heart, and Gonzales had to count each one to find out which color had more. The color with the most coins would ultimately reveal the baby's sex.
After counting more than 100 coins, which Gonzales called a "group effort," she discovered there were more blue coins than pink.
"It's a.....!!!!! Kellan really had me on a roller coaster with this one 😂," Gonzales captioned the sweet clip.
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The pair announced they are expecting their second baby with a sweet reveal video on Instagram earlier this month.
In the clip, Gonzales surprises her husband with her pregnancy news by sending him an iCal invitation with their baby's future due date. The clip then transitions to a photoshoot of the couple with Ashtyn Lilly, who's wearing a "big sister" onesie.
"2 under 2 in 2022 🙌😍 God is Good! Babies are the Best! Love you forever and always @brittanylynnlutz," the actor captioned the video.
Gonzales shared the same video on her Instagram page, writing, "2 UNDER 2 IN 2022!!!! Some might say we're crazy, we say we're crazy BLESSED 😍❤️."
Lutz and Gonzales welcomed their first child together on Feb. 22, 2021. Gonzales announced Ashtyn Lilly's arrival with three polaroid pictures of herself and Lutz holding their newborn.
"The day she came into the world it was snowing, raining, and freezing, but that night she was born and we woke up to sun, clear skies, and winter melting away," the first-time mom wrote in the announcement.
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She continued, "It was so symbolic considering this time last year was literally winter for our souls only to be met one year later with the brightest sunshine."
Prior to Ashtyn's arrival, Gonzales shared an emotional Instagram post, reflecting on a pregnancy loss she suffered in early 2020.
"One year to the day later I sit here 35 weeks pregnant with the most incredible gift in my belly," she wrote in part. "My marriage stronger than ever. My faith stronger than ever. And to think I'd have none of this had I not walked through that."