Hi all.. Question: do garters probe the same as other colubrids??

I just picked up a (supposibly) trio of Checkered garters.. Albino female, het female and normal male.. the females are clutch mates..but the het female is 3 times the size of the albino..no joke.. length and width(fat sucker)..

The albino was probed by seller as female.. I watched her probed, but took word at it.. The albino female is the same size as my albino male..which is normal size for male...

Is it possible one is just a better eater?? The lady kept them and fed them all together..and normal male is scrawny.. but what would be reason for the albino to be so much smaller then sibling?? Other then being MALE...

Granted I paid in MICE so not out too much money, but...

Billie