My baby also the same since 3rd month to 6-7th month. Each time we went back to the PD for follow up her weight is dropping to the 5-10th percentile. Luckily now she’s drinking well and when she see the milk she’s happy. What I did last time was I resorted to coaxing her to sleep and feed her while she’s sleeping. That’s the only way to make her drink. We did ask the pd about her weight and drinking issue - which is also why she started solid early. So long as your baby weight is not falling below the minimum percentile, it’s fine. Anyway check if your baby is having teething now. My baby had her first tooth erupt close to 5th month, which is also why she’s not drinking.
Anonymous