Police were aware of the conviction when Daniel vanished aged seven in 2003 in Great Yarmouth, Norfolk, but it was never made public...
The railway worker’s marriage to Daniel’s mum Paula ended soon after police told her of the conviction early in the search...
Rumours of his conviction had circulated online but it was only confirmed after the Sunday People made an application to Preston Crown Court this week.
As the conviction happened before 1997, Entwistle never appeared on the Sex Offender Register.
A document released on the orders of a judge said: “David Entwistle was upon his own confession convicted upon indictment of sexual intercourse with a girl under 13 years on March 26, 1987, at the Crown Court at Preston. He was sentenced to six months.”