Commentary by Sarah Elizabeth Schaffer DeRoo, MD, FAAP
Published December 2023

At 4 years old, children have a ferocious curiosity. They are engaging with and exploring the world around them. At this age, children are telling stories with rapidly expanding language abilities, are able to dress and undress themselves, and maintain bowel and bladder continence (although they may not be night trained). During this time, children are learning about and testing boundaries, engaging in imaginary play, and establishing friendships with peers.

Keywords: 4 year old; school readiness; influenza vaccine; flu vaccine; dyslipidemia; media use; nutrition; covid-19; developmental milestones