The makings of a presidential ticket began in an unusual spot six months ago: a Minnesota abortion clinic.

At the time, it was a historic visit for Vice President Kamala Harris — no president or vice president had ever made a public stop at one. But the visit laid the groundwork for Harris to connect with Minnesota Gov. Tim Walz and learn about his interest in reproductive health, an issue Harris has taken the lead on during her White House term.

At first glance, the 60-year-old governor might not seem the most likely of political surrogates to talk about abortion and pregnancy. But Harris found a partner who has a track record of increasing abortion access in his state and can speak comfortably about his own family’s struggles with infertility.

Already, Walz has captivated crowds in Pennsylvania and Wisconsin with the story of his daughter’s birth, made possible through in vitro fertilization treatments. The procedure involves retrieving a woman’s eggs and combining them in a lab dish with sperm to create a fertilized embryo that is transferred into the woman’s uterus in hopes of creating a pregnancy.

His wife, Gwen, went through seven years of fertility treatments before their daughter arrived. Phone calls in those years from Gwen often led to heartbreak, he’s said, until one day when she called crying with the good news that she was pregnant.

“It’s not by chance that we named our daughter Hope,” he told crowds in Philadelphia and again Wednesday in Eau Claire, Wisconsin.

The couple also has a son, Gus.

Walz fired up the arena in Philadelphia on Tuesday, his first appearance as Harris’ vice presidential pick, with a warning to Republicans.

“Even if we wouldn’t make the same choice for ourselves, there’s a golden rule: mind your own damn business,” Walz said to a crowd that roared in response. Harris smiled, clapping behind him. “Look, that includes IVF. And this gets personal for me and family.”