https://www.pennlive.com/coronavirus/2022/12/pfizer-asks-fda-to-clear-updated-covid-19-vaccine-for-kids-under-5.html

Pfizer is asking U.S. regulators to authorize its updated COVID-19 vaccine for children under age 5 — not as a booster but part of their initial shots.

Children ages 6 months through 4 years already are supposed to get three extra-small doses of the original Pfizer COVID-19 vaccine — each a tenth of the amount adults receive — as their primary series. If the Food and Drug Administration agrees, a dose of Pfizer’s bivalent omicron-targeting vaccine would be substituted for their third shot.