You need an incubater.. its a specail inclosure for eggs att all sizes..
most breeders would have them..
but ofcourse incubaters dont come cheap.
maybe a heat mat? maybe wrap a heat mat around with a thick
towel in a dark dry closed spot like draw?
google on how to look for an egg if this doesnt help?
Well.. we have chickens, and when theyvbeen fertlized we put them under a heat lamp.. I dont know if it same about a baby eggHow do I care for a baby weasel?