AHMAD 4077:
from Abū ʿUbaydah b. ʿAbdullāh from his father —
“Whoever sends fourth three of his children who had not reached the age of puberty, they will be a strong fortification for him against the Fire.” Abu Dharr said: “I sent forth two.” He said: “And two” Ubayy bin Ka’b, the chief of the reciters, said: “I sent forth one.” He said: “Even one.” (Using translation from Ibn Mājah 1606)
أحمد ٤٠٧٧:
عن ابو عبيده بن عبد الله عن أبيه —
قَالَ رَسُولُ اللهِ ﷺ مَنْ قَدَّمَ ثَلَاثَةً لَمْ يَبْلُغُوا الْحِنْثَ كَانُوا لَهُ حِصْنًا حَصِينًا مِنَ النَّارِ فَقَالَ أَبُو الدَّرْدَاءِ قَدَّمْتُ اثْنَيْنِ؟ قَالَ وَاثْنَيْنِ فَقَالَ أُبَيُّ بْنُ كَعْبٍ أَبُو الْمُنْذِرِ سَيِّدُ الْقُرَّاءِ قَدَّمْتُ وَاحِدًا؟ قَالَ وَوَاحِدٌ وَلَكِنْ ذَاكَ فِي أَوَّلِ صَدْمَةٍ
hadithunlocked.com