grandchild

noun

1. A child of someone's child.

   “...he fell into amazement when he thought of the Herculean labours those fifteen pairs of hands had performed: of the cows they had milked, the butter they had made, the gardens they had planted, the children and grandchildren they had tended, the brooms they had worn out, the mountains of food they had cooked. It made him dizzy.”

   “Legendary NFL quarterback Joe Montana and his wife confronted a woman suspected of trying to kidnap their grandchild Saturday, according to the Los Angeles County Sheriff’s Department.”

   “A couple in India are suing their son and daughter-in-law – for not giving them grandchildren after six years of marriage.”