Sayyiduna Ibn Abbas (may Allah be pleased with them both) said: The Messenger of Allah (peace and blessings be upon him) passed by a woman who was in her litter (howdah). She brought out a child and said: "O Prophet of Allah, is there Hajj for this one?" He (peace and blessings be upon him) said: "Yes, and you will have a reward (for it as well)."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10970