Serena Williams’ daughter might only be months old but she is already outshining her world champion mother.

The 36-year-old tennis star became a first time mother last year - and even won the Australian Open while pregnant with her daughter, Alexis.

Serena - who is married to Reddic co-founder Alexis Ohanian - shared a photo of herself with her seven-month-old daughter as they cooled off beside a swimming pool together.

Beaming Serena posed while holding her daughter as they both dipped their feet in the water as they sat at the side of the pool - and fans of the sports champion were overjoyed by the adorable photo, reports the Mirror.

‘My gosh she is the cutest Bub I have seen,’ one fan gushed in the comments section of Instagram after Serena uploaded the photo online.

‘Awe she is already a [star], so adorable. She has the best leader,’ gushed another.

While another offered a compliment for Serena herself, writing: ‘Serena you look fit and fabulous! Both so beautiful.’

Serena and her husband Alexis have already set up an Instagram account for their daughter, Alexis, which has already racked up almost 310,000 followers (20,000 more than the young girls’ own father’s account).

Fans can find an abundance of photos of the tiny tot modelling an impressive wardrobe of baby clothes, cosying up to her parents for selfies, and even starring on the cover of Vogue magazine.

The feed features amusing anecdotes ‘from’ the tot herself, with the caption of her Vogue post stating: ‘My mom and dad always did tell me to dream big. But for now I am told I am the youngest Vogue cover ever at 3 months! Love you guys.’