be able to change birth county from one suggested

When you type in a birth city, the county is suggested with it.  That is okay, but I want to add another feature.  I want to have a feature where you can edit and type in a new county regardless of the one suggested with that particular city.  Some cities have a county for within city limits and outside in the surrounding area it is a different county.  So if someone was born right outside the city limits in a different county but still claim that city as their closest city of birth, you should be able to put in the exact county they were born in.  Otherwise, you are stuck just going off of their county suggestions which would be wrong for some people.