Chest infection in my small baby? What should they be doing?

Hard to say. You get the most from this site when you provide adequate background information and ask a related question. Small ?, Chest infection ? These are nonspecific terms. You are welcome to start over. The age & gestation of baby if premi. What kind of chest infection & how it was diagnosed ? Is baby home or hospitalized ? These are all relevant issues. Each post is never linked.
Depends on age. Of your child, and if he/she is hospitalized. Hopefully you are in the care of a board certified pediatrician who will order the appropriate tests and medications. Also depends on if your child is premature.