Mariatu is eight years old. She attends Walter Halls Primary School in Nottingham. She studies cello with Sarah Huson-Whyte, and she also plays piano.
Mariatu has appeared on several television and radio programmes with her siblings, including BBC World Service, Al Jazeera TV, Channel 4, BBC 1 The One Show and the BBC4 documentary, Young, Gifted and Classical.
She has performed with the Kanneh-Masons in a series of concerts in Antigua and Barbuda, and also for The Prince of Wales and The Duchess of Cornwall in March 2017.