The congregations of mothers and their babies are held to remember the 6-month-old infant son of Imam Hussein (AS), Hazrat Ali Asghar (AS), who was mercilessly killed on the day of Ashura in the battle of Karbala in the year 680 AD.
Mothers dressed their babies in special green and white clothes, which are said to resemble the clothing of Hazrat Ali Asghar. Babies also wear a headband with the name of Ali Asghar written on it.
According to Davood Manafipoor, secretary of the World Ali Asghar (AS) Assembly, 6250 places in Iran and 45 other countries hosted the gatherings on Friday.
In Tehran, the gathering was held at the 100,000-seater Azadi Stadium.