A woman lifted up a young child of hers toward the Prophet ﷺ during his Hajj and said, "Messenger of Allah, does this child have a Hajj?"He replied, "Yes, and you will have a reward."
حدثنا علي بن محمد ومحمد بن طريف قالا حدثنا أبو معاوية حدثني محمد بن سوقة عن محمد بن المنكدر
رفعت امرأة صبيا لها إلى النبي ﷺ في حجته فقالت يا رسول الله ألهذا حج قال نعم ولك أجر
[Its isnad is sahih] Tirmidhi transmitted it, in Hajj, chapter on what has been said about the Hajj of a child, hadith no. 924, from Muhammad bin Tarif through this route, and he said, "Gharib."