His younger brother Rhys has played football for Manchester City and captained the Welsh under-21 side.
His older brother, Mick, captained Cork to the All-Ireland title in 1911.
Donnellan's brother, John, captained Galway to the All-Ireland title in 1964.
His brother, Charles Doig, Jr., played 196 games for East Fremantle and also captained the club.
His brother, Jack, played Test cricket for England and captained Kent.
His younger brother Rolph Grant later captained the West Indies' side.
His brother, Michael, has also played for and captained Denmark.
His brother and nephew, both named William, also played for and captained Cheshire.
Xavier's adopted brother, Vergyl Tantor, captained the vanguard ballista and moved it into position.
His brother, Morten, has played for and captained Denmark.
