These were the eldest three sons of Ethelwulf and Osburga and all reigned before their more famous brother Alfred the Great.
Ethelbald (died 860)
Ethelbald was left in charge while his father went on a pilgrimage to Rome in mourning for his wife. On his father's return though Ethelbald fell in love with his father's new young bride, Judith, daughter of Charles the Bald. He married her the year his father died, which greatly upset the church. Ethelbald died two years later, having been forced to give her up, and is buried at Sherbourne Abbey.
Ethelbert (died 865)
Little is known of poor Ethelbert though he reigned as sub-king in Kent, Essex, Sussex and Surrey, as his father had done before. He succeeded his brother for a reign of five years, then died, presumably unmarried, and was also buried at Sherbourne.
Ethelred I (died 871)
Ethelred spent all his time ruling from the battlefield, fending off the marauding Danes, where he was assisted by his younger brother Alfred. He was married to Wulfthryth and had two sons, Ethelhelm and Ethelwold. When Ethelred was fatally wounded in the battle of Merton, his sons were still both children and therefore deemed too young to be king. Alfred succeeded to the throne instead. Ethelred is buried at Wimbourne Abbey.
Of the sons, Ethelhelm is rumoured to have been the man who became Bishop of Wells in 909 and Archbishop of Canterbury in 914, dying in 923. Ethelwold rebelled against his cousin Edward the Elder, but was killed in 904 while trying to usurp the throne.