"We’re so excited to finally be able to announce that Mia and I are the new Ambassadors for Palmolive Naturals Haircare! We had so much fun working together on this campaign. So proud of my girl! #palmoliveanz," she announced to her 131K followers.
Fans were quick to send messages of congratulations to the mother and daughter duo.
"The best news congratulations Bec & Mia!!! Palmolive are lucky to have such amazing ambassadors ❤❤❤," one person wrote.
While another commented: "Beautiful, mother and daughter 🌹🌷."
As previously reported on WHO, 12-year-old Mia made her modelling debut in April.
Also taking to Instagram last month, proud mum Bec, 34, shared a professional headshot of her daughter and captioned it: "Yes, she is this grown up now!🙈 #mia."
Can you believe how grown up she is?