As for those kids that go away and keep coming back, I heard it described tonight as "boomerang kids"! Both of mine were: daughter did a 4-year degree away from home, but then a 2-year postgrad course in our home city, so, guess what, she lived back with us again. Son was more like a yo-yo: one year away, couple of years back, another year away, back home for final uni year when flat got too expensive.....!
Now they both live in their own respective homes, but in same city as us, which is very nice!