This isn’t a dumb question at all.

It is likely those who’ve died physically can be aware of others here. Whether they visit can depend on many things. It may not be productive for the growth of those still here for them to visit or they may not have a need to do so.

We can reincarnate here many, many times. It is possible that we could be born again to the same parents we had in a past lifetime if they met again in a future incarnation. More likely it will be the same group having different roles though.