Complex sentence: Blair and his brothers Gavin and Ryan were members of the band Snubrocket (later re-named Fifth Avenue), which was one of 30 that appeared in the music video clip for TISM's song "Thunderbirds Are Coming Out" in 1998.
Split into simpler sentences: Blair and his brothers Gavin and Ryan were members of the band Snubrocket (later re-named Fifth Avenue). The band was one of 30 that appeared in the music video clip for TISM's song "Thunderbirds Are Coming Out" in 1998.