More polls (46) 4 months, week 3: How many times did your baby wake you last night? But do you know exactly what to expect across all realms of your little one’s growth and health: physical, social-emotional, speech and language, cognitive and nutrition?. Three months: babbling! should be getting. Also keep in mind that all babies grow at his or her pace.If you do not see any of the milestone of baby month by month as stated, it is completely normal in baby’s development. Observing baby development stages month by month, is certainly a great source of joy to all parents. Most of the internal organs and systems are fully developed, but the lungs still need time to mature. advertisement | page continues below.