The story sparked calls for better sex education for Britain's young people
Alfie Patten, the boy who was reported to have fathered a child when he was 12 years old, is not the baby's father, DNA tests have shown.
Alfie, now 13, from Eastbourne in East Sussex, told a national newspaper in February that he believed he had made his 15-year-old girlfriend pregnant.
But the tests established in March that a 15-year-old boy from Eastbourne is the father of Chantelle Stedman's baby.
The results of the DNA tests have been made public following a judge's ruling.
The judgement also reveals that Alfie was "extremely distressed" about the results of the test.
'Children having children'
The real father of the baby is not being named by the BBC but an interview with his own father conducted in February, before DNA tests had confirmed his identity, has been broadcast.
In it, the teenager's father, himself a single parent, says his son would have to stand by his responsibilities.
"You can't just leave the mother to bring it up on her own with the parents, even if it's only a matter of giving them money every now and again," he told BBC Radio 5 Live's Victoria Derbyshire show.
"I've also said to him, if it comes to it, and it is his, he has to have his responsibilities, and I don't mind playing the dutiful grandfather."
He added that he had no idea his son was having sex, saying he was too embarrassed to talk to him about it.
Pictures of Alfie, holding the baby he believed to be his newborn daughter, caused a furore when they were published in the Sun in February and renewed calls for better sex education in Britain.
Politicians were moved to speak out about the case.
Tory leader David Cameron said he found the sight of "children having children" extremely worrying.
And Children's Secretary Ed Balls said it was an "awful" and "unusual" case.