Al-Sha'bi (may Allah have mercy on him) said that Sayyiduna Ibn Abbas (may Allah be pleased with them both) wrote to Sayyiduna Ali (may Allah be pleased with him) asking him about six brothers and a grandfather. Sayyiduna Ali (may Allah be pleased with him) replied: Treat him as though he were one of them, and erase my letter.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الفرائض / 12438