"Το μωρό πίνει γάλα."

[Mark958555]

Would "infant" be o.k. for "baby"?

[faKJ]

Probably. It is a synonym of baby but it is officially translated into Greek as βρέφος. It has a lot of meanings.

[GeoEco]

No one would use the equivalent (βρέφος) in Greek in such an utterance, unless it were in a scientific text or e.g. in a paediatric lecture. Since it says "μωρό" here, baby is the only accepted term, I believe