The Child of the Carnival [L’Enfant du carnaval]

A foundling is left in front of the home of a rich aristocratic bachelor during the Nice carnival. The marquis adopts the child but soon finds that he cannot cope, so he employs a nanny who turns out to be the child's real mother. Just as the two have fallen in love and there is a happy ending in sight, the woman's husband - long thought dead - turns up.