Catherine was born to Malayali Frank Mario Alexander and Tresa Alexander in Dubai.[1] She said, "I don't speak fluent Malayalam, it's mostly English that we speak at home. At the age of 14, Catherine did some amateur modelling for fashion design graduate students.[5] After coming to India, she modelled for Nalli Silks, Chennai Silks, Fast Track, Josco Jewellers and Deccan Chronicle. She has also shot for Srikantadatta Wodeyar's Maharaja Calendar and had participated with Prasad Bidapa in many ramp shows in many cities.