DNA tests have shown that 13-year-old Alfie Patten did not father a child born in February to a 15-year-old girl.
The results, revealed in high court last month and made public Monday, showed the father is 15-year-old Tyler Barker, who lived near baby Maisie's mother Chantelle Steadman in Eastbourne, southern England, AFP reported. Barker was 14 when Steadman became pregnant.
Five more boys in Eastbourne, East Sussex, also said they slept with the girl.
The story of Alfie, who was initially believed to have fathered a baby when he was 12, has renewed calls for Britain to get its teen pregnancy epidemic under control.
Prime Minister Gordon Brown said previously he was worried by the story and that the government did all it could to prevent teenage pregnancies.
Alfie, who is also from Eastbourne, was "extremely distressed" when told he was not the father, according to court documents.