This story is connected to the fourth avatar of Vishnu, Narasimha (the half-man, half-lion).
Prahlada was the son of Hiranyakashipu, a great demon who conquered the demigods and took over the universe. Once while Hiranyakashipu was engaged in austerities, trying to become immortal, the demigods captured his wife, Kayadhu who was at the time pregnant. The demigods were fearful that the child within her womb would be as terrible as his father, and were considering killing the child. However, the great saint Narada appeared and reassured the gods that the child was destined to be a great saint.
Narada gave shelter to Kayadhu in his ashram and instructed her in spiritual knowledge. The baby in the womb, by that time conscious, listened very carefully and thus became inspired in spiritual life by the grace of a saintly person. Thus, even though Prahlada was born of a materialistic family he was inclined to God’s service even from the beginning of his life.
For the rest of the story, please go to STO-304
The Festival of Holi.
Whilst Hiranyakashipu was trying to kill his son – quite unsuccessfully (see STO-304) – he asked his sister, Holika to carry her nephew to the flames of a blazing fire. Holika had won a boon from Agni, the fire god, that she would not be harmed by fire. Thus she happily consented to the brother’s wishes. Prahlada as ever, was fearless and constantly meditated on Lord Vishnu. Once in the fire, it was Prahlada who was protected by Agni, while Holika perished. During Holi, Hindus remember how God protects his devotees by building and circumambulating bonfires while chanting God’s names.