PHILADELPHIA (CBS) — First Lady Jill Biden is encouraging the vaccination of children ages 5 to 11 in the fight against COVID-19. The first lady visited the Children’s Hospital of Philadelphia on Friday morning before she headed to Oklahoma for another event.

Biden shook hands with kids at a vaccination clinic at CHOP on Friday.

READ MORE: WATCH LIVE: Montgomery County, Pennsylvania Officials Join With Area Hospital Leadership To Discuss COVID Surge

Each kid received a sticker proudly displaying their vaccination status.

“I’m a teacher, I’m a mom, I’m a nana,” Biden said, “so I want to talk to all the parents out there.”

The first lady is continuing a nationwide push, urging parents and guardians to vaccinate kids 5-11 now that the COVID-19 vaccine is readily available to the youngest and most vulnerable population.

“The vaccine has been thoroughly reviewed and rigorously tested,” she said.”It’s safe, it’s free and it’s available for every single child in this country ages 5 and up.”

Doctors at CHOP are continuing their tireless efforts to combat the ongoing pandemic and its effects on children. To date, they’ve administered 22,600 first vaccination doses to CHOP patients, but they stress more work still needs to be done.

READ MORE: WATCH LIVE: Philadelphia Health Department To Provide A COVID-19 Update

“COVID-19 is currently ranked as one of the top 10 causes of death in children aged 5-11 years across the country,” one doctor said. “Here at CHOP, of all the children we’ve cared for with COVID-19, over 175 of them have been critically ill.”

The first lady was joined by Pennsylvania Gov. Tom Wolf, who continues to promote pediatric vaccines.

The latest statistics from the Philadelphia Department of Public Health show that 11.5% of kids 5-11 years old have received one dose of the vaccine. That’s 13,332 children so far in the city.

“I think we’re doing pretty well,” Wolf said, “and I’m really heartened by the progress we’ve made on pediatric vaccines.”

Every weekend CHOP is hosting pediatric vaccine hubs at clinic all throughout Philadelphia.

MORE NEWS: Dump Truck, 3 Other Vehicles Involved In Chester County Crash On Route 30

Meanwhile, Philadelphia officials reported the first confirmed case of the new COVID-19 omicron variant on Friday afternoon.