On June 17, 2022, the U.S. Food and Drug Administration (FDA) extended emergency use authorization of the Moderna COVID-19 vaccine and the Pfizer-BioNTech COVID-19 vaccine for children as young as 6 months old. Previously vaccination was only authorized for children ages 5 years and older. This approval was granted following an evaluation of clinical trials of each product looking at safety and efficacy in children ages 6 months and older. Compared to the two-dose regimen for older age groups, the Pfizer-BioNTech COVID-19 vaccine, given to children ages 6 months through 4 years in three smaller doses, exhibited similar immune response. An initial dose is followed by a second dose after three weeks, and a third dose should be administered after another eight weeks. The Moderna COVID-19 vaccine follows the two-dose series schedule for both adults and individuals 6 months through 17 years old and showed similar immune response in all age groups studied. Doses are given one month apart, but the strength changes based on age range. For both products, the most commonly reported side effects were similar to those seen in other age groups, including pain, redness and swelling at the injection site, fever, muscle pain and fatigue. Additional reports in younger children included irritability/crying, loss of appetite and swelling/tenderness of the lymph nodes. The Centers for Disease Control and Prevention (CDC) recommends that all children ages 6 months through 5 years receive the vaccine, even if they have already had a COVID-19 infection.