Dave, it looks as though your nephew and, possibly, your niece had lots of fun! I'm with Elizabeth about that last photo! Those planes are fun when they really go, but so often they do make nose dives.
There's nothing quite like the freedom to be that most children in loving and safe families feel. I hope you've shared your photographs with them - and their parents, Dave. I know that when our daughter was little I took tons of photographs...and a parent can never have too many.