Well, when you go onto your second generation, you get a password in the "family" catagory .. the password allows you to visit the parent that had flown away at midnight. Well, when you're on your third generation, you get a password for your grandparent. You take that password to your "grandparents" house and enter the code. Then your visiting the parent of the parent that just left! lol. It's kind of confusing! Hope I helped!
~Tama_Mama27