ʿUyūn akhbār al-Riḍā
Hadith 321321 - وَبِهذَا الإسناد قالَ: قالَ رَسُولَ اللَّهِ صَلَّى اللهُعَلَيْهِ وَآلِهِ: اغسلوا صبيانكم من الغمر فَإِنَّ الشَّيْطان يشم الغمر فيفزع الصبي فِي رقاده وَيتأذى بِها الكاتبان.
31-321 According to the same documentation, God’s Prophet (S) said, “Wash the dirt off of your children’s faces since Satan will sense it and cause your children to be afraid while they are asleep. Then the guardian angels appointed for your children will be hurt.”