Gordon Brown wept when he talked of the death of his daughter Jennifer during a TV interview, it has emerged.
The Prime Minister's eyes filled with tears as he told Piers Morgan he knew that his newborn daughter was not going to survive.
She died in 2002 aged 10 days after suffering a brain haemorrhage.
The exchange took place in front of a live studio audience and is due to be broadcast on ITV next Sunday.
Mr Brown also spoke of his three-year-old son Fraser's battle with cystic fibrosis.
Other topics reportedly covered during the interview include an admission that he occasionally lost his temper, confirmation of "explosive" rows with former PM Tony Blair, and the fact that Mr Blair had secretly promised to hand over power to him - but that the timing lay with his predecessor.
It has long been speculated that the pair struck a leadership deal at Granita restaurant in Islington following the death of former leader John Smith.
The programme next Sunday night heralds a new series of Piers Morgan's Life Stories. Previous guests have included X Factor judge Dannii Minogue and tennis player Boris Becker.