As long as each file has a proper include guard, it won't matter how many times you've included a file. I'd much rather have the preprocessor figure out when and where to include a file than do it myself. Maybe this was a significant performance issue in 1989, but it shouldn't be anymore.
That said, you should only include files that are direct dependencies. There's no need to include stdio.h in every other file.
As long as each file has a proper include guard, it won't matter how many times you've included a file. I'd much rather have the preprocessor figure out when and where to include a file than do it myself. Maybe this was a significant performance issue in 1989, but it shouldn't be anymore.
That said, you should only include files that are direct dependencies. There's no need to include stdio.h in every other file.