Hadithcore
Al-Adab Al-Mufrad, 146
hasan· Al-Albani

Jabir ibn 'Abdullah said, "I heard the Messenger of Allah, (ﷺ), say, 'If anyone has three of his children die young and resigns them to Allah, he will enter the Garden.' We said, 'Messenger of Allah, what about two?' 'And two,' he said." Mahmud ibn Labid said to Jabir, "By Allah, I think that if you had asked, 'And one?' he would have given a similar answer." He said, "By Allah, I think so too."

حَدَّثَنَا عَيَّاشٌ، قَالَ‏:‏ حَدَّثَنَا عَبْدُ الأَعْلَى، قَالَ‏:‏ حَدَّثَنَا مُحَمَّدُ بْنُ إِسْحَاقَ قَالَ‏:‏ حَدَّثَنِي مُحَمَّدُ بْنُ إِبْرَاهِيمَ بْنِ الْحَارِثِ، عَنْ مَحْمُودِ بْنِ لَبِيدٍ، عَنْ جَابِرِ بْنِ عَبْدِ اللهِ قَالَ‏:‏ سَمِعْتُ رَسُولَ اللهِ صلى الله عليه وسلم يَقُولُ‏:‏ مَنْ مَاتَ لَهُ ثَلاَثَةٌ مِنَ الْوَلَدِ فَاحْتَسَبَهُمْ دَخَلَ الْجَنَّةَ، قُلْنَا‏:‏ يَا رَسُولَ اللهِ، وَاثْنَانِ‏؟‏ قَالَ‏:‏ وَاثْنَانِ، قُلْتُ لِجَابِرٍ‏:‏ وَاللَّهِ، أَرَى لَوْ قُلْتُمْ وَاحِدٌ لَقَالَ‏.‏ قَالَ‏:‏ وَأَنَا أَظُنُّهُ وَاللَّهِ‏.‏

References2 variants
In-Book Reference
Book 8, Hadith 4
English Reference
Book 8, Hadith 146