The Holt family was very successful and wealthy. Philip D. Holt's grandfather was George Holt Sr., a merchant and cotton broker who founded the family's fortunes. He was father to five sons and one daughter. He financed the construction of the original India Buildings in Liverpool and founded Blackburne House, also in Liverpool, as a school for girls.
George Holt Jr., the second of the five sons, was also a merchant and ship owner. He lived at Sudley House in Liverpool and founded Liverpool Institute High School for Boys. He has a building dedicated to him at the University of Liverpool.
Robert Durning Holt (Liverpool, 11 October 1832 - 1908) was an English shipowner, cotton-broker and local politician and father to Philip Durning Holt of Sibbersfield.
He was the youngest of five sons of merchant George Holt and Emma Durning and worked first in his father's cotton-broking business. His uncle was Alfred Holt, founder of Blue Funnel lines. Robert Durning Holt married Lawrencina Potter, daughter of railway magnate Richard Potter and Lawrencina Heyworth. His son. Philip's brother was the national politician Sir Richard Durning Holt (MP for Liverpool)
Robert suceeded to his father's firm and entered local politics in the Liberal interest, becoming leader of the party. He was a councillor from 1877, and was the last Mayor and first Lord Mayor, from 1892-3, in the first Liberal dominated Council for 50 years. He was deputy chairmain of the Libraries, Museums and Art Gallery Committee in Liverpool between 1899 and 1903 and later between 1905 and 1908. He declined both Aldermanship and Baronetcy.