 His younger brother Henry Liddell, Rector of Easington (1787–1872), was father of a younger Henry Liddell, co-author (with Robert Scott) of the monumental work "A Greek-English Lexicon", and father of the Alice who inspired "Alice in Wonderland".He succeeded his father in the baronetcy and to the family estates at Ravensworth Castle and Eslington Park and to extensive coal mining interests in 1791.He was High Sheriff of Northumberland in 1804 and served as Tory Member of Parliament for County Durham between 1806 and 1807.