Bill and Melinda Gates have been married 25 years, raised three kids, are worth $100.9 billion, and run a namesake philanthropic enterprise boasting a $50.7 billion endowment— but still find the time to do dishes together.

The Gates family always does the dishes after dinner together to remind their kids that home responsibilities aren’t just women’s work, Melinda said in a conversation with Business Insider US editor-in-chief Alyson Shontell.

Read more: Melinda Gates reveals the secret to a strong marriage and the surprisingly simple answer to the world’s toughest problem

The key to a strong marriage is when partners participate in household chores equally, whether that be laundry or packing lunch, Gates told Business Insider. Women traditionally are seen as responsible for doing unpaid housework. Gates discusses the issues tied to unpaid work and gender inequality in her book, The Moment of Lift.

When you can share that responsibility, the marriage becomes more balanced.

“One thing in society we have put on women is we don’t talk about how difficult it is to raise children,” Gates said in the interview. “We just assume women are going to go do it. It takes time and it takes energy, right?”

Here’s a look at the marriage between Bill and Melinda, and how they make their relationship work.