It shouldn't take too long for them to get adopted out. Of course, if you want to speed it up - couldn't you just adopt one from the spouse to be and then put it up for adoption yourself before the attachment forms?
It just makes me sad to put them up for adoption. I know they're just little pixel pups, but still. But no worries, it's been a couple of Sim days now and I think they should be gone..
Oh, and another question: Say you've completed all your tasks and you bring in the heir and life goes on for your little clan. What happens if a burglar comes and steals some of the things in your mausoleum from your completed generations? And then *gasp* gets away with it? (I have a bad habit of wandering away when my game is loading and coming back to discover that several hours have passed while I was gone. And since that's just me being stupid and not a glitch, I'd have to live with the consequences.) Can you just replace the replaceable things (skill items)? And I don't even know if burglars steal things like skill certificates or job rewards/trophies, but if so, what would you do about that? Or would you have failed?
I've already got my little security alarms all set up, but just on the off chance something happens.
But wait, do we actually have to be able to get into our mausoleum? Can I just build a basement, throw all my necessary items in, and never add stairs?