The American actress shared photos of her son Brooks and her daughter Scarlett taking it in turns to cuddle their new sibling Grey at their first hospital visit.
Little Scarlett, who turns two in March, was pictured holding a bottle to the newborn's mouth, attempting to feed the tot. Meanwhile Brooks, four, cradled the baby in his arms. "I got this," he sweetly told his mum.
Molly's daughter Scarlett attempted to feed her baby brother
Molly, 43, admitted that she "might have cried" during the siblings' first encounter. She and husband Scott Stuber welcomed their third child on Tuesday, but Molly wasn't discharged until the weekend.
The Las Vegas star gave a sweet shout out to her doctor and opened up about her emotional journey.
"I got this," Brooks sweetly told his mum
"Thank you Dr Michelle Hakakha for being the best doctor a girl could ask for... keeping me calm and sane through all of my freak outs and letting me cry and stress when I needed too," wrote Molly, who gave birth at celebrity favourite hospital Cedars-Sinai Medical Center. "And to the amazing team at @cedarssinai hospital for taking such great care of me and Baby Grey."
Molly also used Instagram to announce her baby's birth, writing: "Welcome to the world Grey Douglas Stuber 1.10.17. Words do not express how grateful and happy we are to have another piece of magic added to our little tribe!"
Molly and Scott welcomed their son on Tuesday
The model has previously spoken about her surprise at getting pregnant again. Making a choked-up appearance on her official YouTube channel, Molly said: "This is happening. This is like our Hail Mary. This is such a true surprise. I think that's why I am so emotional."
She announced her pregnancy in August, adding that it hadn't been plain sailing. "I have never had more morning sickness in my life. I have been sick from the moment I wake up to the moment I go to bed," she said.