A young girl placed in the foster home made abuse allegation against a teenage family member in 2007.
She was removed from the home, but a boy and a girl remained with the foster family.
The report on RTE's Prime Time found that the second girl also made abuse allegations, four years later.
She was removed from the home, but the boy remained with the family for another year.
A prosecution is being taken in relation to the abuse allegations – most of them relating to the second girl.
