If you were to arrange a skydive for your 18th birthday, who's the last person you'd think to take with you? How about your 88-year-old great grandfather?

But then again, if your elderly relative was as much of a dude as Nathan Detrick's great granddad Bob, then why the hell not? The old man clearly enjoyed the experience, as did Nathan's 43-year-old dad, and 65 year-old granddad.

Here's hoping we're all still that up for it when we reach his age.

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