[1] Seoige was born in An Spidéal, County Galway, the youngest of four children, to parents Mairtín and Philomena.
After completing her Leaving Certificate, she was hired by TnaG to present a film show called Hollywood Anocht.
When Hollywood Anocht ended Síle became TG4's weather girl and continuity presenter, and after two years she moved on to host a children's programme called Cúla4.
She produced a four-part series for RTÉ called Coiscéim and appeared with The Devilins on a compilation CD SnaG-05 featuring bands from Ireland singing in Irish language.
In the summer of 2005, she took part in the first You're a Star series, in which she raised over forty thousand euro for Galway-based charity, Cope.
She has appeared as a guest presenter on travel programme No Frontiers and co-presented season one of RTÉ's entertainment series Class Act with Aidan Power.