Defrosted milk

mb314

How long after milk is defrosted do I need to use it?  I send four bottles to daycare - two are "fresh milk" and two are frozen from my stash.  I typically defrost and refrigerate the two bottles the night before.  I haven't been marking which one is which. Yesterday, he only took three bottles, so one was left over.  If it was formerly-frozen milk, is it still good the following day (so about 36 hour after it was defrosted)?