Musnad Ahmad 529:7

Abu al-Nadr Hashim ibn al-Qasim narrated to us, he said: Hariz narrated to us, from Shurahbil ibn Shuf'ah, he said: I heard Utbah ibn 'Abd al-Sulami that he heard the Messenger of Allah, may Allah bless him and grant him peace, saying: "There is no servant whose three children die before they reach the age of puberty, except that they will meet him at the eight gates of Paradise; he will enter through whichever of them he wishes."