What a cool challenge. I got 173. I doubt my 12 year-old nephew could get 20 either. I have a bit of an advantage in that I have been to nearly 100 of them.
Dude, if your niece has any problem, it’s that she went and dropped a huge spoiler for Avengers 3 on you out of nowhere–that’s just darn rude! 
And of course, you courteously passed along to us without a word of warning, ARGH.
(I’ve sent a heads-up to the mods to hopefully get a spoiler note added to the thread title. But next time, think!)
Also re: the sun & New Zealand – by a weird coincidence, I was on Amtrak last week and happened to dine with a lovely couple from NZ (little boast: they were impressed I guessed their country of origin right off, since apparently most Americans guess the UK or, if they’ve got better ears, Australia). Anyway, point is, during our convo, they mentioned that skin cancer is really bad over there due to the ozone layer issue. So it does seem to be a thing, sadly.
Title edited to indicate Avengers 3 spoiler