Babies this age are learning how to interact with the world around them. To get your attention, your baby might cry, fuss, or squeal. To get a better view of the room, babies may use newfound strength to pull up on their arms while lying on the belly. Doctors use certain milestones to tell if a baby is developing as expected. There's a wide range of what's considered normal, so some babies gain skills earlier or later than others. Babies who were born prematurely reach milestones later. Always talk with your doctor about your baby's progress. Here are some things your baby might be doing: Communication and Language Skills babbles with expression as a way to get your attention smiles, laughs, squeals, and blows bubbles begins to coo in response to your coos stares at your mouth as you speak has different cries for hunger, tiredness, or pain Movement and Physical Development rolls from front to back begins to reach and grasp for objects bring toys to the mouth, often with a two-handed grasp has good head control when sitting holds up the head and chest, supported by the arms, while on tummy Social and Emotional Development smiles when something pleasing happens, such as a belly tickle, and responds to affection initiates social interaction with coos or babbles self-soothes, such as sucking on a fist when hungry gets excited when a caregiver approaches Cognitive Skills (Thinking and Learning) is easily distracted by surroundings (for example, a baby that used to be focused on nursing or sucking from a bottle is now interrupted by the slightest noise) starts to predict routines (for example, stops crying when placed in a nursing position or flexes hips in anticipation of a diaper change) repeats behaviors that produce a desired effect, such as batting a toy to move it grasps and examines own hands explores toys by grasping, mouthing, and looking at them When to Talk to Your Doctor As a parent, you are the best observer of your baby. Share your concerns — even little ones — with your baby's doctor. Always tell the doctor if your baby: regularly babbles, but then suddenly stops cannot maintain head control when held in a supported position doesn't notice when people enter the room doesn't swipe at nearby toys doesn't respond to voices or other pleasing sounds Also, if you ever notice that your baby has lost skills he or she once had or shows weakness on one side of the body, tell your doctor. Back to Articles Related Articles Your Child's Checkup: 4 Months Find out what this doctor's visit will involve and what your baby might be doing by the fourth month. Read More Your Baby's Growth: 4 Months Your baby is growing in many ways. Here's what to expect this month. Read More Your Baby's Hearing, Vision, and Other Senses: 4 Months Your baby is working on all five senses, understanding and anticipating more and more. How can you stimulate your baby's senses? Read More Communication and Your 4- to 7-Month-Old Your baby's range of sounds and facial expressions continues to grow, and your baby is also imitating sounds, which are the first attempts at speaking. Read More Feeding Your 4- to 7-Month-Old Is your baby is ready for solid foods? Learn how and when to get started. Read More Learning, Play, and Your 4- to 7-Month-Old Your infant will learn to sit during this time, and in the next few months will begin exploring by reaching out for objects, grasping and inspecting them. Read More Medical Care and Your 4- to 7-Month-Old Because your baby begins to show his or her personality during these months, your questions may move from simple sleeping and eating concerns to those about physical and social development. Read More Movement, Coordination, and Your 4- to 7-Month-Old At this age, kids are learning to roll over, reach out to get what they want, and sit up. Provide a safe place to practice moving and lots of interesting objects to reach for. Read More Sleep and Your 4- to 7-Month-Old By this age, your baby should be on the way to having a regular sleep pattern, sleeping longer at night, and taking 2 or 3 naps during the day. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.