Hugo Rawlinson's sister's engagement was noted in Richard's posting of 25 December 2021 at https://groups.google.com/g/peerage-news/c/AzlvOybR1hM/m/Sc0ZuPxdCQAJ. Their father, John Lawrence Rawlinson (born 4 VIII 1959), is also an old Etonian and a former first-class cricketer. He was the second of the three sons of Sir Anthony Keith RAWLINSON, KCB (5 III 1926 - 22 II 1986) by his 1956 marriage to Mary HILL.
Sir Anthony Rawlinson was the only son of Dr Alfred Edward John ("Jack") RAWLINSON (17 VII 1884 - 17 VII 1960), who was the second Bishop of Derby from 1936 to 1959, and his wife (married 1 VII 1919), Mildred Ansley ELLIS, OBE, daughter of the Rev Percy Ansley ELLIS (c.1855 - 4 VI 1944).
Hugo Rawlinson's mother, Mrs Penelope Anne Jocelyn RAWLINSON, née LETTS (20 X 1957 - 2017), was a sister of Quentin Richard Stephen LETTS (born 6 II 1963), the journalist and theatre critic; their paternal grandmother, née Eveleen Frances Calthrop BONNER (28 III 1903 - 27 IX 1969), was the daughter of the High Court judge Sir George Albert BONNER (9 III 1862 - 27 IV 1952).