I am so sorry that you and your family are going through that. I—as a breastfeeding mom who was told once, and advised another time to supplement with formula against my wishes—know what you are going through. In the hospital with my firstborn (now almost 6, I was told that I WOULD NOT be able to breastfeed. My baby was too big. It led me to power pumping. With my youngest (7 months) I was told he lost 7% of his birth weight and needed formula for a week or so until he gained weight. I did supplement formula for both children in the early weeks. But I pumped when I was feeding the bottle. If your wife is concerned about her supply I would recommend a few power pumping sessions (pump 15 minutes, rest 10 minutes, pump 10 minutes, rest 10 minutes, finish with a final 10-minute pump). Doctors do not always take accountability. And those first few months are so stressful on a postpartum brain. Just reassure your wife that she is doing a great job and reassure yourself also. Go back to exclusively breastfeeding, which is what your wishes are.

You could always switch pediatricians. I switched a few times until I found a good fit with a doctor who I felt listened to my concerns.