Northern Irish musical legend who had four UK No. 1 hits with Bill Martin and more than 20 albums certified platinum.
He started a rock 'n' roll band while studying at Queens University.
He and Bill Martin penned the Bay City Rollers' UK chart-topper Shang-A-Lang and Saturday Night, their American No. 1 hit.
He came from a musical family with his father accompanying family musicals on the fiddle and his wife on the upright piano.
He wrote songs for renowned artists like Van Morrison, Jerry Lee Lewis, and Tom Jones, among many others.