My grandmother doesn’t get hungover

This woman is 5’3 and 102 pounds and she’ll drink 10 beers and a few shots with a cocktail or two on the weekends and she’ll be up early the next morning firing up the pancakes before I’m even awake and I don’t even drink. I’ve never seen anything like it, when I have drank in the past to that extent I feel like absolute shit when I wake up. The reason I don’t drink is because of hangovers. I’m only 25 and she is 80!!! Wtf guys what’s her secret she doesn’t even know