Even a child is rewarded for Ḥajj
A woman lifted up her child and said: Messenger of Allah, would the child be credited with having performed the Hajj? Thereupon he said: Yes, and there would be a reward for you.
رَفَعَتِ امْرَأَةٌ صَبِيًّا لَهَا فَقَالَتْ يَا رَسُولَ اللَّهِ أَلِهَذَا حَجٌّ قَالَ نَعَمْ وَلَكِ أَجْرٌ