Jill Biden thanks moms for being 'strong and resilient' in a celebratory Mother's Day message

• First Lady Jill Biden on Sunday delivered a message of encouragement to moms nationwide.
• "I know how hard you're working, and I want you to remember that you're strong, you're resilient," she told moms in a video message.
• Working moms were hit hard by the pandemic, struggling to balance caretaking with day-job demands.

First lady Jill Biden on Sunday offered moms everywhere words of support and gratitude to commemorate Mother's Day.

"The pandemic has affected every part of our lives, challenging us and changing us like we never could have imagined. Whether your kids are 2 or 52, this year has been a tough one for moms," she said in an posted to Twitter.

"I know it feels like so much is on you - it was a lot even before the pandemic," Biden continued. "And just when you thought you had little left to give, you gave more. Because you're a mom, and that's what moms do. I'm proud of how we've come together even when we've had to remain apart, supporting each other in countless ways."

The coronavirus pandemic has brought on economic hardship and financial devastation for millions of Americans and small businesses.

Among those hardest hit were working moms, who've struggled to take care of their kids during at-home learning periods while working their day jobs.

At the onset of the pandemic, about 13 million or about 45% of mothers who live with school-age children were not actively working, according to Census data. In normal times, about 70% of mothers with school-age children were.

The dramatic drop in working mothers during the pandemic represents more than just a symptom of a weakened economy, experts say. It also means that the American workforce isn't designed to support mothers.

"I know how hard you're working, and I want you to remember that you're strong, you're resilient, and you're doing an amazing job," Biden said. "From one mother to another, I see you, and I thank you."