Socio emotional development is not a physical change, however it can be observed by referring to the different milestone changes or skill development in your baby. For school readiness it is important to nurture and provide to your baby a platform for socio emotional growth. Babies are naturally inquisitive and are explorers by nature. They learn how to communicate what they need in their own way.
When your baby was just born, most of his time was spent sleeping, however now your baby may be curious and responds. They become more alert, can look into your eyes, can hear sounds and respond to your voice. They transition into an active state of mind. They also start crying, feel sleepy, learn to communicate when they are hungry or may cry when they need a diaper change etc. They learn to communicate and are quite excited when you cuddle him.