Rosie Jane Day (born 6 March 1995) is an English actress, writer and director. She is known for playing Mary Hawkins in the Golden Globe nominated Starz and Sony Pictures TV series Outlander and Sarah Jessica Parker's daughter in the comedy film All Roads Lead to Rome. She currently stars as Tina Pemberton in Sky One's Living the Dream, alongside Phillip Glenister and Lesley Sharp, and the 2018 Summit Entertainment feature Down a Dark Hall alongside Uma Thurman. She is also an ambassador for the teenage mental health charity stem4.
Day has been acting since childhood, both on stage and on screen, following in the footsteps of her older sister. It was at one of her sister's auditions that she was spotted by a casting agent and given her first role, at the age of 4, in BBC's Hope and Glory. In that same year, Day and her sister played two of the Dudakov children in Maxim Gorky’s play Summerfolk at the Royal National Theatre in London. She soon became a successful child actor on British television playing roles such as young Tess Elliot in ITV's medical drama Harley Street in 2008, and in theatre including at the Royal Court Theatre and Palace Theatre.