Question about mortgage late fees

[Ann]

This may sound like a very ignorant question but I was wondering if I make a mortgage payment that is after the grace period but before actually being 30 days late can those late fees be tacked on to my account if I did not reaffirm the mortgage? My thinking is if I am say 20 days late making that payment because of an emergency would it matter for me to pay the extra if I am not being reported? I do have some late fees attached from before I filed.