How much longer will we get to enjoy camping with our son?

Our kids are 9 and 13 and they enjoy camping, but sometimes want to stay home for other activities. Because of this, I've done several solo trips, which I actually enjoy quite a bit, lovin' the peace and quiet! Still, I'm the traveling spark plug and tell them all the time, my plan is to drag them to as many sights and adventures as possible while still on this side of the earth's surface. Hopefully they cherish the memories.