Forged Death Certificate for Adopted Child?

Here's a fun one...

I'm working on a friend's ancestry and have come across a very odd situation. Her grandmother knew her adoptive name, birth date, and birth location. I have found the grandmother's original birth certificate. However, I've also found a death certificate that says the grandmother died at 3 months old. The death certificate says the child was interred at a local cemetery. Making this odder, the birth record says it was corrected about 40 years after the fact, but I can't find any corrections.

Has anyone ever seen actual evidence of death certificates -- including interment details -- being forged to conceal adoptions? I can't think of any other explanation. I've definitely heard of forged birth certificates, but to legally kill off a child only to have her resurface shortly after seems very odd to me.