Mother’s Day, holiday in honour of mothers that is celebrated in countries throughout the world. In its modern form the holiday originated in the United States, where it is observed on the second Sunday in May. Many other countries also celebrate the holiday on this date, while some mark the observance at other times of the year. During the Middle Ages the custom developed of allowing those who had moved away to visit their home parishes and their mothers on Laetare Sunday, the fourth Sunday of Lent. This became Mothering Sunday in Britain, where it continued into modern times, although it has largely been replaced by Mother’s Day.