It is narrated from Hazrat Uqbah bin Amir (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) said: Whoever's three real children die and he shows patience before Allah regarding them, Paradise becomes obligatory for him.
Hadith Referenceمسند احمد / مسند الشاميين / 17298
Hadith Gradingحکم دارالسلام:حديث صحيح ، ابن لهيعة سيئ الحفظ، وقد توبع