Take it how I mean it and nothing more!?

My son is only 2 years old but I've noticed he is a lot bigger *down there* than other little boys that I have seen from changing their diapers. My husband is QUITE well indowed (we're talking an easy 9in. soft). Do you think it's hereditary? Or did my son just get lucky like his dad? If you respond with perverted comments I will report you. Only serious responses please.