The European Court of Justice in Luxembourg has ruled that non-EU citizens should have the right to residence in the European Union if their children were born in the bloc.
It made the judgment following a case involving a woman from Venezuela.
The announcement has caused some alarm among those in the UK who wish to control immigration rates.
The judgement resolves the problem of one family where the mother – a Venezuelan – was refused welfare rights for her European born child due to her lack of residency rights after separating from the Dutch father.
The court argued that any threat to the mother’s right to remain in the EU would deprive the child of the “genuine enjoyment” of his or her own rights under European law.
The ECJ’s ruling has been described as further “interference” in national court judgments about migration by some who voted for the UK to leave the EU.