Sayyiduna Anas bin Malik (may Allah be pleased with him) said: I was beneath the she-camel of the Messenger of Allah (peace and blessings be upon him), and its saliva was dripping on me. I heard him (peace and blessings be upon him) saying: "Allah Almighty has given everyone who has a right his right, and there is no bequest for an heir."
This hadith has been narrated through other routes, all of which are not strong. Reliance is on the first hadith, which is the narration of Ibn Abi Najih from Ata from Ibn Abbas, and on what al-Shafi'i mentioned from the report of the people of the maghazi, together with the consensus of the generality (of scholars) on holding this view; and Allah knows best.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوصايا / 12541