The photo captures their beautiful family in a candid bonding moment, with one of the girls looking adoringly at her little brother, and Bonnie sporting a happy grin.
Audrey and Evie are just smitten with their baby brother, where Alex recently shared another photo of his girls grinning while they held Max.
"Unbridled joy with the girls getting to know their little brother," he said.
Alex and Bonnie announced the arrival of their son via the Today show's official Instagram on August 16, with the social media account sharing the first first pics.
"IT’S A BOY! 👦💙" the post was captioned. "Alex and his beautiful wife Bonnie welcomed a healthy baby boy early yesterday morning! Congrats guys 💓"
Alex then shared another post to his own account and wrote: "We couldn’t be happier. Our healthy, happy little boy came into the world at 1.08 on Sunday morning weighing 3.7 kilograms.
"After 41 and a half weeks it was well and truly worth the wait! Name TBC and can’t wait for his big twin sisters Audrey and Evie to meet him, boss him and shower him with cuddles. I marvel at Bonnie’s strength especially in these very trying times. Just amazing. Mum and baby Cullen recovering well."
He then followed with another post, sharing a close-up photo of their baby boy, and finally revealed his name.
"Introducing Max Thomas Campbell Cullen. @bonbonred and Max are doing well and we are happy beyond words. Thank you so much to everyone for all your lovely messages and well wishes."
The family are no doubt trying to make the most of the lockdown situation by spending plenty of time together and creating wonderful memories.
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