SACRAMENTO, Calif. — This week, President Joe Biden warned the number of COVID-19 cases could begin to increase again if the number of people getting vaccinated continues to decline.

The nation is seeing millions of fewer inoculations a day compared to just a few weeks ago and now the administration is turning its attention to children. For California, the Western States Scientific Safety Review Workgroup independently reviewed the coronavirus vaccines approved by the Food and Drug Administration for children.

Karen, a West Sacramento mother, explained how she was elated to hear the Pfizer vaccine had received authorization for ages 12-15. She said she let her 12-year-old daughter Lily choose whether she wanted the vaccine.

Lily took the freedom of choice one step further by choosing to take part in the Pfizer vaccine trial for adolescents. They requested their full names not be disclosed for fear of backlash from the anti-vaccine community.

For Karen and Lily, their decisions are personal. At the end of last year, Karen’s father passed away in December from COVID-19. It was the same month the COVID-19 vaccine was approved for emergency authorization. Karen explained how her father just missed it.

"The hardest part was not being able to be there for him," she said. "I got a chance to go down to the hospital just to say ‘goodbye’. But other than that, I was just so isolated from him."

Karen added that her husband and two children helped her through the loss. Later that month, Lily decided she needed to do what she could to help defeat the virus. With her parents’ consent, she joined the Pfizer vaccine’s trial for adolescents.

"I was so sad, like I didn’t even get to say goodbye to [my grandpa]," said Lily. "And it was really hard, and so it’s important that not just at-risk people get vaccinated, but that kids do too. It’s going to protect those at high-risk, like my grandpa was."

Months later, the FDA has now approved the Pfizer vaccine for adolescents 12 to 15 years old. Lily just found out she had received a placebo during the trial, so she received the real shot Tuesday morning.

Dr. Sally Goza, who is the immediate past president of the American Academy of Pediatrics and works closely with the Biden administration, praised children like Lily because kids 12-17 represent an increasing proportion of coronavirus cases in America.

“It’s showing about 20% of new cases are actually in children under the age of 18, and so that's a change from the beginning of the pandemic,” she said. “This is our way out of the pandemic."

Dr. Goza added that children have carried the burden of lockdowns.

“The year of COVID has been a hard one," she said. "I’ve seen my patients having anxiety and depression. The younger children are having social issues where they don’t feel comfortable around other children. We’ve seen the increase of suicide ideation in our office just escalate drastically over the last year. It was already rising before the pandemic. They’re sad a lot of the time. They don’t feel comfortable around their friends anymore because they haven’t been around them in so long, and so it’s just really hard to see. These kids have essentially lost a year.”

Vaccination rates have fallen. One month ago, about 3.3 million doses were given each day. The latest data shows an average of 1.7 million doses a day, a drop of about 48%. It’s a concern to the Biden administration, which announced plans last week to boost rates with new on-campus vaccination sites and a partnership with Uber and Lyft to provide free rides to sites.

“Well, I think it’s exactly what we need if we are ever going to be back to the way things were,” Karen said, adding that families shouldn’t take the vaccine for granted.

It could have saved Karen's dad if it were created just weeks before. She noted that she’s proud of her daughter for stepping up amid the pandemic to help others.

“The thought for me of my daughter being one of the people that helped make vaccines available for younger kids, it just made me very proud,” Karen said.

Lily has focused a lot on her community since the pandemic started. She started to sell beaded bracelets with friends to send proceeds to food banks and health organizations. Lily said she wants to be a pediatric oncologist when she gets older.