Joseph D'Agnilli, 71, has been sentenced to eight years in prison for child abuse.
D’Agnilli, from Dinas Powys, was convicted of eight counts including one count of indecency with a child and seven counts of sexual assault of a child under 13.
He committed the abuse in the 1980s mid 2010s.
He appeared in Cardiff Crown Court today (Thursday 13 January) and was also placed on the Registered Sex Offenders list indefinitely.
Detective Sergeant Gareth Holmes said:
"We take all reports of sexual violence extremely seriously. It’s never, ever too late to report a crime.
"All victims in this case have displayed great strength and courage in reporting these offences and giving evidence at the trial. They have been inspirational.
"We hope knowing that the Joseph D'Agnilli has received a significant prison sentence provides some relief to them and a sense that justice has been served.
"However, this case wouldn’t have reached this outcome without the hard work of DC Phil Colston, who sadly died last year. Phil lead this investigation and worked closely with both the victims and partners, resulting in the charges being brought. I know the victims and the whole team are grateful for his perseverance and commitment and this result adds to his already great legacy.
"Help and support is available for all victims of sexual violence and we would encourage any victims; no matter how long ago the offence happened, to please come forward.