Over the years,John Caldwell Kaia Gerber has had a front row seat to Hailey Bieber's personal journey.

And now, the supermodel is over the moon for her pregnant pal as she prepares to welcome her first baby with husband Justin Bieber.

"I'm just so, so happy for them," Kaia told E! News at Palm Royale's Official Emmy FYC Event with Apple+ May 11, adding that the couple will be "wonderful" parents. "Hailey has such a maternal quality about her, I've known her so long." (For more from Kaia's interview, watch E! News May 13.)

The Bottoms actress was among the first celebs to react to Hailey's pregnancy announcement on May 9, commenting on her Instagram post, "my heart!!!!!!!"

And Kaia wasn't alone. The pair's friends and family, including his mom Pattie Mallette, also showered them with love.

"So I have been waiting for this day," Pattie said in an Instagram video. "And now that they have shared it, I can finally celebrate with y'all. Oh my gosh, I'm gonna be a grandma! Oh my goodness."

"Justin and Hailey, you are gonna be the best parents ever, and I am so excited," she told the duo, who wed in September 2018. "Oh my goodness. Praise God."

Meanwhile, Hailey's dad Stephen Baldwin also sent his well-wishes. "Love you guys," he wrote on Instagram May 9. "Blessed beyond words."

"Praise God," he added. "Let's get ready to have some fun y'all."

To see more celebs react to Hailey's pregnancy news, keep reading...

—Reporting by Monica Fink.

After the couple announced they're expecting their first baby together on May 9, their friends and family sent their well-wishes.

"I love you guys sooooo much!!!!"

"We are so so excited can’t wait can’t wait what a blessing!!!!!"

"ahhhh here come the tears again."

"i love you guys!!!! ahhhhhhhh."

"Yayayayyaaaaaa."

"THANK YOU JESUS."

*cry face emoji

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"Omgggg so happy for you both."

"chillieee williessss I love you soooo much!!!!"

"love you both so much."

"Yayyy!!! Congratulations!!!"

"Congratulations!!! Sending so much love so happy for you both."

"AHH IM PREGNANT AT THE SAME TIME AS HAILEY OMG YAYY CONGRATSSSS."

"EEEEEEEEEEEEEEEEEEEEEEEEE!!!!!! You are going to be an amazing amazing mommy oh boy get ready!!! So exciting so happy for you both!!"

"blessing."

"Cutiesssss. Congratulations babe."

"Congratulations love."

"Omggggg Congratulations."

"OMG sooo happy for you guys, congratulations."

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