There is a documentary made in Germany on Youtube about this. A Spanish doctor who was responsible for stealing babies from women who had just delivered was finally brought to court in 2018 but not prosecuted as, under the statute of limitations, his crimes were seen as having happened too long ago.
It was said that, under Franco's regime, babies were taken from left wing families and given to right wing families to be "brought up properly". I don't know how much truth there was in this rumour.
It has been estimated that as many as 300,000 babies were abducted both during and ,for some time, after the end of the Franco regime.
