Aethelhelm or Æþelhelm was the younger son of Ethelred of Wessex (Æþelræd).
Both he and his brother were too young to inherit the throne in 871 and it passed to their uncle King Alfred the Great (Ælfred) who granted them both lands. On Alfred's death in 899 his elder brother Aethelwald contested the succession and was killed. However, Aethelhelm did not and seemed content to remain Earlderman of Wiltshire.
Aethelhelm had two children: Elfleda of Wessex (c.890-918) and Aethelfrith of Wessex (c.900-927). Elfleda became Queen consort to King Edward the Elder (c.871-924) while Aethelfrith lived the life of a common landlord.
Aethelfrith's son, Eadric of Wessex, was granted possession of Washington in the South Downs of west Sussex. His son, Aethelwerd of Wessex (c.930-998) is known as "the Historian". Aethelmar Cild (c.960-1015), son of Aethelwerd, was a benefactor of Eynsham Abbey. His son was Wulfnoth Cild (c.983-1015) who was Thegn of Sussex but is otherwise obscure. Godwin was son to Wulfnoth and Harold (Harold II) was the son of Godwin.
Harold Godwinson, who later became King Harold II, was according to this genealogy of the House of Wessex - a fact which may have been hidden by the Normans. Indeed, after Harold's death, the death of his brothers, and the death of Edgar Ætheling the other sons of the Aethelhelm branch of the Wessex family may be the only source of an extant heir to the House of Wessex.
With reference to: Godwine Biography