important? >> we do a lot of vaccinations for kids to keep them safe. getting them vaccinated will bring infection numbers down across the community for everybody. >> reporter: pfizer's vaccine, the same formula used for adults, just a smaller dose the white house saying they will prepackage the child size viles more than 25,000 doctors' offices, 100 plus hospitals and tens of thousands of pharmacies nationwide will be ready for quick distribution. >> one, two, three. >> reporter: seven-year-old lydia and her five-year-old sister bridgette participated in the vaccine trial. was there any hesitation >> none whatsoever meghan and i have both already been vaccinated, and we felt extremely comfortable just personally. >> i think we also want to teach them that science is important and also giving back and kind of stepping up. >> we were scared if we got covid and now it will probably protect us from covid