My LO is 4 1/2 months and at her 4mo appt she weighed 13lb 5.5 oz. I was told this was the 50%. She has been all over the place on the charts but mostly decreasing in % but my ped said it was completely normal and healthy growth esp for a bf baby
I believe this was calculated using a chart for breast fed babies. Maybe that is the problem and not anything with your son or your supply?