Be honest..... if you dont know....tell him your not quite sure..but you have been asking people and they had this to say.......... Then tell him what you think.... Another nice thing would be to ask him.... ask him to go inside and see what his heart tells him.....
Kids are amazing and will usually find a very quick and firm connection to the wisdom of their heart and soul... tell him he can also ask before he goes to sleep, and he might have a dream about his question :).. I bet he'll have some things to teach you!!
and if he does.....be sure to come back and let us know....!!! :)