A few years ago, my sister, Jan, was diagnosed with lymphoma. The doctors were hopeful, but the treatment was hard: six weeks in isolation for stem cell replacement therapy. Like so many families, my three other sisters and I carried fear and anxiety alongside Jan. We worried about her pain. We worried about her loneliness while in isolation. We worried about the odds of her treatment’s success.

But we didn’t worry that her insurance wouldn’t cover the high cost of her care.

Medicine saved my sister’s life, but something outside of the hospital helped save her too: the Affordable Care Act.

Jan built her career as a waitress, and though she had insurance when she was diagnosed, it was the kind we saw too much of before the ACA, and it didn’t cover her treatment. But thanks to the law, she found a great plan she could afford. And even though she was already sick, the insurance company was required to cover her.

It’s easy to take for granted just how much changed when we passed the ACA. Twenty million additional Americans got covered. Companies could no longer discriminate against people with pre-existing conditions. Annual and lifetime limits were ended, and so much more.

As I travel around New Hampshire and the rest of the country, I’ve heard stories similar to Jan’s. I recently visited Riverbend Community Mental Health in Concord, where people told me how critical Medicaid expansion — made possible through the Affordable Care Act — is to addressing the substance misuse crisis in their communities. I’ve met entrepreneurs who told me they were able to start businesses because they had options outside of employer plans. And I’ve met cancer survivors who can only get insured because of the ACA.

But it’s also easy to forget how close this law came to being just another failed attempt at health care reform. The fact is that its fate was determined by only a handful of votes in Congress. When many began to doubt it could pass, President Barack Obama said to my husband, Joe, his vice president, “You’ve got to go over to Capitol Hill. We’ve got to get this done.” And they did.

Since then, the ACA has been under constant attack. The Trump administration has shown that it will stop at nothing to get rid of the very protections that saved my sister. Since 2017, the number of people without insurance has gone up. And we hear more and more stories about families who are once again stuck with impossible options: choosing between paying bills and seeing a doctor, avoiding needed emergency care or rationing medications.

We can’t go back. But more than that, we must go forward and build on the progress we made.

As president, my husband is going to increase tax credits so families will pay less for their premiums and have lower deductibles. He’s going to allow Medicare to negotiate drug prices so that Americans don’t pay huge amounts of money for drugs the rest of the world buys at reasonable rates. And he’s going to create a public health insurance option like Medicare so that if you can’t find a plan you can afford with an insurance company, you’ll have a high-quality public alternative.

No issue has been more divisive over this last decade than health care, and yet, for people like my sister, getting this right can literally mean the difference between life and death. That’s why we need a president who knows how to bring people together. We need someone who will build on the progress we’ve made, not start from the beginning.

That’s Joe Biden. He’s won battles like this before and he can do it again. And he has the vision, determination and character to get this done so that all families can stop worrying about the cost of care and focus on what really matters: caring for each other.

Jill Biden is an educator and served as second lady of the United States from 2009 to 2017.