We know that the product of these ages is 72. So what I did is to make a table of guessed ages of the 3 children where the product is 72. I, then added these ages. If it was given, it would be easy to answer the question. Mark pointed out that this information still is not enough. That would mean that there are 2 guesses where the sum is the same. That is 2, 6, 6 and 3, 3, 8. The answer is 2, 6,6 because Bob said "My youngest child called Justice." This would signify that there is only one youngest son.