The pair, who haven’t released their names, feature on posters created by the group Mothers and Fathers Matter.
They said in a statement via Amnesty International that it was a stock photo taken by a photographer friend.
“We were surprised and upset to see the photo was being used as part of a campaign with which we do not agree.”
A Mothers and Fathers Matter spokesperson said: “Like many campaigns, [we have] used a stock photo to give a human face to our message, in this case that children deserve a mother and father wherever possible.
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