COVID-19 vaccination for children ages 6 months to under five years—the only age group yet to be eligible for vaccination—is expected to get underway on June 21, White House COVID-19 response coordinator Ashish Jha said in a press briefing Thursday.

The Food and Drug Administration is now reviewing data from Moderna and Pfizer-BioNTech on their respective vaccines for the young age group. The agency will convene its panel of independent expert advisors to review the data on June 15 and vote on whether the vaccines should be granted emergency use authorization.

If the panel votes in favor of authorization, the FDA will likely grant authorization quickly. Once that happens, shipments of federal supplies of the vaccines will begin going out to states for distribution. But, before they can go into little arms, the Centers for Disease Control and Prevention will need to have its own advisory committee meeting to review the data and vote on a recommendation. And for the final step, the CDC Director Rochelle Walensky will need to endorse the recommendation.