Dang I was gunna say 18 but she looked so big I had to throw in an extra two lol. Congrats on all the new little ones sorry about the ones that didn't make it.
Hopefully she just ate one that had some other issue, and doesn't devour the whole litter. My mother in law has her brother as a pet, and I'm thinking maybe she's just a chunker. He's a little fatty lol.