Best recognized as the younger sister of singer and internet sensation Sophia Grace Brownlee.
She made her internet debut shortly after her birth on her sister's Instagram account, appearing in the picture captioned "A new princess has arrived, my baby sister."
Her parents run her popular Instagram account which has accumulated more than 50,000 followers. She also has a YouTube channel called My Sister Belle.
Her parents are Dominic and Carly Brownlee. Her father is a writer, producer, and music consultant.
In June 2016, she met and posted a photo to Instagram with rapper Silento.