I am currently using Twenty Ten and Twenty Twelve as parents for my custom child themes that I create for my clients. Recently I have upgraded these default themes as follows:
Twenty Ten (1.4 to 1.5)
Twenty Twelve (1.0 to 1.1)
I am aware that the changes in these updates will apply to my child themes too but what about the files I have copied from the parent and edited (i.e. header.php, footer.php, etc). I found the links below which show the changes that have been made between versions:
Should I manually make all these changes to the files I have COPIED from the parent theme to ALL of my client websites? I am worried something might break if I don't.