Born to a mother from the Moonshae Isles and a father who may have exaggerated his bastard half-cousin connection to his patriar family name, Roísín grew up with a slew of siblings looking for a way out. Upon discovering her talent for singing, her mother put Roísín in music classes, the price of which often meant the other children went without. Still, trying to increase their social capital, Roísín's mother dragged her to every society get-together to put her on display and try to secure some notoriety, if not a patron or a position.
A notoriously cruel noblewoman told them at one of these parties that her Róisín would never succeed looking so plain, and offered her a beauty potion—but when Róisín drank it, to the delight of the revelers, she just turned entirely pink. Still, the prank ended up working, because the fascinating and talented young girl was soon scooped up by the opera house as a regular performer after rumors of the incident began circulating.
For years, Róisín's performances made her the primary breadwinner of her family, and she was trained in classical musical instruments, singing, and dance (like, whatever the Faerûnian equivalent of ballet is). Unfortunately, like in irl history, the arts scene also served as a subtle escort service for the rich opera house patrons, and by the time Róisín was nearing adulthood, she was acutely aware of what would be expected of her as an entertainer of the patriars, on and off-stage. Confronted with her apparent life-long purpose as a plaything of the rich people she simpered to during her performances, Róisín packed a bag with a portion of the money she had earned for her family and her instruments and left the city proper.
Initially, she eked out a living performing at taverns and even Sharess' Caress, expanding her repertoire from classical music to bawdy shanties and the occasional original composition. She made friends with other performers and built her stage persona into something unique and genuine, not forced and stuffy. Rumors of the pink singer started to make their way back to Baldur's Gate, so to avoid the notice of her family, Róisín threw her lot in with one of the traveling circuses that stopped by the outskirts of Wyrm's Crossing and hit the road.
Here, she flourished, and found friends and a home like she'd never had before. Even as a mainly musical performer, everyone had to be ready to step in and do anything as-needed, so Róisín was trained in knife-throwing, fire-swallowing, fortune-telling, and charm-casting. Life on the road hardened her a little, but she would have never left if given the choice.