When he inherited the baronetcy and the family estate of De Grendel upon his father's death, he decided to experiment with viniculture and winemaking. Sir David was a director of Graaffs Trust and The Milnerton Estates Limited.
Sir David is survived by his wife Sally and his four children, the eldest of whom, De Villiers, succeeded him in the baronetcy and farming at De Grendel Estate.[2]