It is narrated from Sayyiduna Uthman bin Abi al-As (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "A man three of whose own offspring have died before him in (the state of) Islam has taken a strong shield against the Fire."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 8313