The dealer I go to gets new stuff every week....generally....sadly he had nothing this week
I had the same talk with my neice and nephiew when my father died, I forget how old they where at the time. It's amazing, they actually confront a funeral better than their father does now, as demonstrated when my mother passed a few years later.
Too many to list, boys who have been sheltered form nudity tend to become overly curious. This can lead to a handfull of problems when they act on that curiousity, most predominate in all boy, in the same age bracket households (parents not included). This can also apply to households where the female sibling is in a different age bracket as well. The same applies to females to a slightly lesser degree.
When my neice(8) and nephew (10) where younger, by sister bathed them together. From this they both understand that boy and girls are different and have seen the difference, having seen the difference they don't think much about it. Kids who dwell on the "what is the difference" question develope a strong desire to find out for them selves.....well you are a guy....how many different ways can you think of to see a naked woman? How many have problems associated with them?
There are many more but....