Rhianna Mae Southby was born on 16th October 2000 and is a right handed wicket-keeper and batter.

She made her county debut for Surrey in 2016 aged just 15 years old, and featured four times as Surrey were promoted to Division One of the T20 County Championship.

In 2018, she was called up to the Surrey Stars in the KIA Super League, and she debuted against Yorkshire Diamonds in the same year before going on to win the KSL twice, in 2018 and 2019.

She then debuted for South East Stars and played all six matches in the 2020 Rachael Heyhoe Flint Trophy, scoring 32 runs and taking one catch and three stumpings.

In 2021, Southby was part of the South East Stars and Oval Invincible squads that won the Charlotte Edwards Cup and Hundred respectively.

In the same year, she scored 124 runs with a high score of 32, along with three catches and stumpings apiece.

In 2022, Southby recorded her first county half-century when she scored exactly 50 for Surrey against Hampshire, before racking up another fifty against Western Storm in the Rachael Heyhoe Flint Trophy.

In November 2022, Southby joined Southern Vipers on a permanent deal from South East Stars, and is one of two wicket-keepers in the squad alongside Chloe Hill. Both players were awarded their first professional contracts with the Vipers in April 2023, and she made her debut for the Club in April 2023 against Sunrisers at The Ageas Bowl.