Son and eldest child of John Patterson Webb and Thursa Alderman Webb. Married to Ettero Lutitia Weddle (1871-1910) on 7 January 1891 in Carroll County, Virginia. Ettero is buried in the Church Alderman Cemetery approximately 1/2 mile west of the John P. Webb Cemetery.
Allen married his second wife, Maggie Jane Webb on 19 December 1911 in Carroll County, Virginia. They are buried together here in the John P. Webb Cemetery.