Cannabis cookie problems.

A friend of mine gave me a bag of 2 cookies. He said I could probly split 1 in half And get backed the same as if i ate tbe whole cookie.
So i did and gave the other half to my mother when i was visiting. The problem is i barely felt anything and she got Blitzed. We ate the cookie at the same time.
So why did she get baked and not me. So the next day I ate the whole 2nd cookie and all I felt was a little bit relaxed but certainly not blitzed.

Most logical guess would be simple tolerance and bioavailability differences between you and her. Mostly tolerance.

If my Mom and I drank the same amount of whiskey, she would be shitfaced and I would be a little tipsy. (She doesn't drink and I am a raging alcoholic).

Perhaps an extreme example but, likely true.