She co-founded the philanthropy with her husband, Facebook founder Mark Zuckerberg in 2015, to build a better world for their first child, daughter Max.
Their goal - to put Dr. Chan's passion for medicine and science and the couple's vast resources toward preventing disease, improving learning and promote social justice and equity.
One year later, they also founded the CZI Biohub, a medical research center that enables scientists from Berkeley, UCSF and Stanford to do collaborative research.
When the Coronavirus pandemic hit, CZI and its Biohub diverted its full attention to solving the COVID-19 pandemic as well as the many challenges it brought on for Americans, especially those who are economically-challenged.
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From her Palo Alto home, Dr. Chan talked one-on-one with ABC7 News anchor Kristen Sze about quitting the job she loved as a pediatrician at UCSF to devote herself full-time to CZI's mission to advance science, education and opportunity.
"We build software, about half of our team is technical," she said. "We do impacting-investing. We support our grantees with capacity-building. We do traditional grant making and we do advocacy."
To date, CZI has committed more than $60 million to support therapeutics development, studying COVID-19 in the Bay Area, supporting distance learning education and more.
Dr. Chan says just because she's a doctor by training does not mean she's overly cautious with 4-year-old Max, 2-year-old August and Mark.
"I'm the opposite of that. I'm like, 'oh you'll be fine,'" she said. "Before coronavirus, I was this free-range hands-off mom. Now they're like, 'Mom why are there so many new rules?'"
Chan says keeping the girls on a schedule helps them cope with shelter-in-place.
Ever the educator, Chan says she does talk about COVID-19 with the girls.
"I try at a 4-year-old level to explain, one in three families with a kid younger than 6 is facing food insecurity, that's a good problem."
Chan has her girls compose letters, print out a list of food that pantries need to drop off at their neighbors.
After a few days, they'll pick up the donations and drop them off at the local pantry.
Dr. Chan says her advice for the Bay Area is to keep up with stay-at-home and social distancing to the extent possible to prevent transmission.
What does that mean for Mother's Day?
"All the moms in our families are taking a flower arranging class together. So there's a way to build community, stay connected and celebrate at the same time. You can't do a good job as a mom unless you have a tribe."