The photo had been placed on a website by a photographer in return for a free photo shoot, with the family's consent.
They told the BBC that while the Mothers and Fathers Matter group had legitimately used their image, they did not agree with its message...
"We got some lovely pictures and we agreed to let the photos to be added to stock. We were just unlucky this time," the father said.
In a statement released via Human Rights campaign group Amnesty International in Ireland the pair laid out their own views on the gay marriage debate, although as non-Irish citizens they were not involved in the vote.
"This family believes that everyone has a right to marry the person they love regardless of their gender," they said.
"And this family would vote Yes [in favour of legalising same sex marriage]."
Good for them.
Quick experiment: The most popular stock photo company is Getty Image's iStock.
Search for 'gay' on their site and what comes up first as 'best match'...