Using thawed milk

bluesky22

Hi ladies! I am new to the bump and hope you don't mind me joining your board. I had my first baby in September and I have heard great things about this site. I have a question about using thawed breast milk. My mom will be watching DS in two weeks for a weekend. I know that once she thaws the milk, it must be refridgerated and used within 24 hours. My question is-can she put a bottle of thawed milk with an icepack in a cooler/diaperbag? Will the milk last or does it solely need to be refridgerated until it is used? Sorry if this has been asked before...I tried to go through the posts but I didn't see it. Thanks for any advice you have!