Sunan an-Nasa'i, Volume 2, Book 19, Hadith 1586 (DarusSalam) ⓘ
It was narrated from Ibn Buraidah that: His father said: "While the Messenger of Allah was on the minbar, Al-Hasan and Al-Husain came,wearing red shirts, walking and stumbling. He came down and picked them up, then said: 'Allah has spoken the truth: Your wealth and your children are only a trial.' I saw these two walking and stumbling in their shirts, and I could not be patient until I went down and picked them up.'"
أَخْبَرَنَا يَعْقُوبُ بْنُ إِبْرَاهِيمَ، قَالَ حَدَّثَنَا أَبُو تُمَيْلَةَ، عَنِ الْحُسَيْنِ بْنِ وَاقِدٍ، عَنِ ابْنِ بُرَيْدَةَ، عَنْ أَبِيهِ، قَالَ بَيْنَا رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى الْمِنْبَرِ يَخْطُبُ إِذْ أَقْبَلَ الْحَسَنُ وَالْحُسَيْنُ عَلَيْهِمَا السَّلاَمُ عَلَيْهِمَا قَمِيصَانِ أَحْمَرَانِ يَمْشِيَانِ وَيَعْثُرَانِ فَنَزَلَ وَحَمَلَهُمَا فَقَالَ " صَدَقَ اللَّهُ { إِنَّمَا أَمْوَالُكُمْ وَأَوْلاَدُكُمْ فِتْنَةٌ } رَأَيْتُ هَذَيْنِ يَمْشِيَانِ وَيَعْثُرَانِ فِي قَمِيصَيْهِمَا فَلَمْ أَصْبِرْ حَتَّى نَزَلْتُ فَحَمَلْتُهُمَا " .
also referenced under: Hadith 1585 (Reference) & Book 19, Hadith 30 (In-Book)