Glenn Quinn
Glenn Martin Christopher Francis Quinn was an Irish actor in television and film, known for playing Mark Healy in the American sitcom Roseanne, and Doyle, a halfdemon, on Angel, a spinoff series of Buffy the Vampire Slayer.
Quinn was born in Dublin, Ireland. He spent his childhood visiting aunts, uncles, and cousins in the United States and spent his teenage years in Cabinteely, County Dublin, Ireland. As a teenager, he played drums in a rock band called Revival, who peaked at supporting Irish AOR Band Winters Reign, and had a demo called How could I knowRock with BOC BLB Radio played on the radio. He also acted in productions at small local theaters. Quinn attended Clonkeen College.
Source: Wikipedia