Twelve-year-old Manoj died on the spot when the blasts hit the Varanasi civil court premises on Friday afternoon.
''His father Jilaid said the boy used to earn around Rs 70 per day to help him sustain a family of nine,'' said a police officer.
Jilaid, who cleans ears and offers massages, is the second money earner of the family.
The 12-year-old resident of Chowkaghat leaves behind his parents and six siblings, including a 20-month-old toddler and four sisters.
The state government has announced a compensation of Rs 2 lakh each to the families of those killed in the latest terror strike in the state. The Centre will also provide Rs one lakh ex-gratia amount to the family of the deceased in the blast.
The serial blasts in Lucknow, Varanasi and Faizabad killed 13 people and injured many more.