There was once a very cruel king called Hirnakashyah who had a son called Prahlad. Prahlad was very good and always prayed to the god Vishnu, which made his father very angry. The King tried very hard to make his son give up his belief in Vishnu.
So the King ordered his sister Holika to take Prahlad in her arms and for both of them to walk into the burning fire. The plan was that Prahlad would die and Holika would be saved because she was protected by the gods of flames. What the King did not know was that the gods' charm over Holika didn't work for one hour during the day. The hour chosen for lighting the fire just happened to be that very hour. When the flames leapt up, Holika died and Prahlad was saved by Vishnu.
Prahlad was so sorry for Holika that he promised to name a festival after her. So now we have the festival of Holi.
An outraged King Hiranyakashipu then decided to kill Prahlad himself. However, the youngster's faith in God would again triumph. A beast with a man's body and a lion's head appeared and attacked the king. His immortality disappeared and the man-lion tore him limb from limb. The moral of the story; Prahlad's faith in God saved him; no man is bigger than God.