He was the fourth son of Thomas Kavanagh of
Borris, County Carlow by his wife Lady Susanna, daughter of
Walter Butler, 16th Earl of Ormonde. He succeeded his elder brother Walter in the family estates in 1813. He married artist Lady
Harriet Kavanagh (née Trench) on 28 February 1825. The couple had three sons Charles, Thomas, Arthur, and one daughter, Harriet or "Hoddy." Their youngest son
Arthur MacMurrough Kavanagh was born with vestigial limbs and Lady Harriet insisted he be raised with the same opportunities as their other children. Following Thomas' death Lady Harriet took their three youngest children travelling in the Middle East for two years. ==References==