"I heard the Messenger of Allah (S.A.W) saying: 'I wanted to prohibit Al-Ghilah, but the Persians and Romans did it, and they did not kill their children.'"
Jami` at-Tirmidhi Book 28, Hadith 41
← Previous Hadith "For fever, and all pains, the Prophet (S.A.W) would teach them to say: Bismillahil-Kabir; a'udhu billahil-'Azimi min sharri kulli 'irqin na'arin, wa min sharri harrin-nar. (In the name of Allah the Great, I seek refuge with Allah the Magnificent from the evil of every gushing vein, and from the evil of the heat of the Fire)"

Jami` at-Tirmidhi Book 28, Hadith 40 Next Hadith → "I intended to prohibit Al-Ghilah until I remembered that the Persians and Romans do that, without any harm to their children."

Jami` at-Tirmidhi Book 28, Hadith 42