Each time a child has taken over the friendship levels have stayed same or gotten better. This child now I have which has grown into an adult (4th or 5th generation )all the friendships have been zeroed. Is this meant to happen?

I had the same thing happen to me a couple days ago. Everyone was at zero and my besie was at zero too. What's the point in making besties if you have to start over each time when your child becomes mayor? Also this time it asked me if I wanted to adopt my adult child to be mayor. What would happen if I said no?

The relationship meters are now reset (in 0.5.42) when the child becomes mayor. The person who was the mayor's bestie was friends with the mayor, not the child. The child needs to make his or her own friends.

Did you try to say no?