Kaia Gerber is "so, so happy" for Hailey Bieber amid her pregnancy

She told E! News: "I'm just so, so happy for them. They're gonna be wonderful parents. Hailey has such a maternal quality about her, I've known her so long."

Hailey first announced the news of her pregnancy with an Instagram post, where she is seen showing off her growing baby bump in a series of photos taken while they renewed their wedding vows.

Among a series of behind-the-scenes snaps, Hailey is seen wearing a white, lace dress that highlights her baby bump while Justin, 30, takes a photo of his wife.

The loved-up couple - who have been married since 2018 - have never made any secret of their desire to have children one day, and a source has revealed that Hailey and Justin are both "thrilled" by the news.

The insider told 'Entertainment Tonight': "Hailey and Justin are thrilled to be expecting a baby together.

"They have wanted this for a long time and can't wait to expand their family and bring a child into the world."

Hailey and Justin have always had a shared ambition to become parents one day.

And the celebrity duo feel that now is the perfect time for them to "take this next step in their lives and relationship".

The source shared: "Hailey and Justin are united and have been on the same page when it comes to parenthood.

"They have experienced so much together as a couple and feel ready to take this next step in their lives and relationship."

What's more, Hailey and Justin are both confident that they'll become great parents.

The insider explained: "Hailey is such a natural caretaker and Justin knows she will be the best mom, and Hailey has always thought that Justin will make an amazing dad. Hailey, Justin, their families and loved ones are so excited for this beautiful blessing."