Abu Hurairah (May Allah be pleased with him) reported: The Messenger of Allah (PBUH) said, "Allah, the Exalted, says: 'I have no reward other than Jannah for a believing slave of Mine who remains patient for My sake when I take away his beloved one from among the inhabitants of the world".
[Al-Bukhari].

Commentary: Child, wife and parents, etc., are the dearest people to everyone. It is a great sign of Faith to accept their death as the Will of Allah, to bear their loss with patience. Wailing and saying nonsense things show weakness of Faith. The reward of patience on such tragedies is Jannah while the result of impatience is displeasure of Allah.