Althorp Papers. Vol. mmccclxxviii. Letters to Lady Spencer from John Evelyn Denison, Viscount Ossington, Speaker of the House of Commons; 1857-1870, n.d.
Althorp Papers. Vols. mdi-mdiv. Letters from his half brother, Charles Robert Spencer, (Bobbie), later 6th Earl Spencer. For Spencer's letters to him, see R1-R9; 1866-1910. Four volumes.
Althorp Papers. Vol. mdix. Letters from: 1. His aunt, Isabella, Marchionness of Exeter; 1851-1874. 2. Brownlow Cecil, 2nd Marquess of Exeter and husband of Lady Isabella. Includes a copy of a reply from Spencer; 1851, 1860-1866.
Althorp Papers. Vol. mdxix. 1. Letters from Charles George, 5th Baron Lyttelton and 8th Viscount Cobham. Includes copies of occasional replies by Lord Spencer; [circa 1863], [1875?]-1889. 2. Letters from Neville Gerald Lyttelton, brother of Charles George, 5th Baron Lyttelton; [circa 1874]-1908.
Althorp Papers. Vol. mdxxv. 1. Letters from Lily Seymour, wife of Horace Seymour; many undated, but circa 1900-1909. 2. Letters from Freda Biddulph, Charlotte Spencer's niece; 1903-1910.