Althorp Papers. Vol. mdviii. Letters from: 1. His uncle, George Spencer, known as Father Ignatius, Superior of the Order of Passionists in London; 1858-1863. 2. His aunt Frances, Dowager Lady Clinton; 1851-1872, n.d.
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.