Narrated Anas
The Prophet (ﷺ) said, "A Muslim whose three children die before the age of puberty will be granted Paradise by Allah due to his mercy for them."
Narrated Abu Sa`id
The women requested the Prophet, "Please fix a day for us." So the Prophet (ﷺ) preached to them and said, "A woman whose three children died would be screened from the Hell Fire by them," Hearing that, a woman asked, "If two died?" The Prophet (ﷺ) replied, "Even two (would screen her from the (Hell) Fire. " And Abu Huraira added, "Those children should be below the age of puberty. "
Narrated Abu Huraira
The Prophet (ﷺ) said, "No Muslim whose three children died will go to the Fire except for Allah's oath (i.e. everyone has to pass over the bridge above the lake of fire)."