In Harriet’s house, you must show respect.

You can take selfies with her bust — five feet of bronze standing sentry at the entrance to the Harriet Tubman Underground Railroad state park in Church Creek. You can wear her likeness on hats. You can even lay your hands on her head.

But, as one seventh grader learned on a recent visit, you cannot lean on Harriet Tubman. Not like that, anyway. Not in front of Mary Dennard, a senior seasonal ranger who has been watching over “Harriet’s House” since it opened in 2017.

“Get your arm off her shoulder,” Dennard, 77, tells the student, who straightens up right away. “That is not a leaning post. That is not respect. You don’t want anyone to lean on you, do you?”

Dennard speaks with the authority of the state corrections officer she was for decades, and as the guardian of Harriet Tubman history that she has been since the 2000s, when residents and later federal and state officials came together to develop a plan for the $21 million state and national historical park.

Her connection to Dorchester County’s most famous resident dates back even further. Her great-great-uncle, Richard B. Lake, was enslaved in the area. When he became free, he purchased land that was part of the Brodess Farm, where Harriet was enslaved. Dennard spent summers on that farm growing up.

She is not the only one at the museum with such a connection. While 70% of the visitors come from outside the Eastern Shore, the 30% that are homegrown often are, in some fashion, connected to Tubman. Many return multiple times for an emotional journey that they often share with Dennard.

Tubman walked off the plantation where she was enslaved in 1849. She risked her life to return 13 times and lead 70 of her friends and relatives to freedom. Yet that’s not the whole story. Many friends, family, and neighbors stayed behind. They kept her secrets, passed her messages, helped her charges. Their descendants remain in Dorchester County today, bearing their forebears’ surnames — among them Cornish, Stanley, Manokey, Meekins, Harris, Molock, and Cephas.

The seventh graders at Mace’s Lane Middle School count some of their families among those ancestors, too.

Bentley Cornish, 12, grew up knowing his family had connections to Tubman’s. Touring the museum got him thinking about a brave act in his small town that changed the course of the country. Dennard’s interpretation of that history, he said, will stay with him.

“She’s open, honest, and she acts like she really wants to teach us this history,” he said.

Brooklyn Copper, who is descended from the Ross and Freeman families, has visited the museum three years in a row, encountering Dennard each time.

Asked what she knew about Tubman, Brooklyn said: “That’s my cousin. She was a slave back in the day, and she saved a lot of people.”

Ask almost anyone walking in what they know about Tubman, and they will repeat some version of this story: Harriet was a slave, she escaped and she took people with her.

It’s true, but incomplete. Dennard’s favorite Tubman arc is her role as the first woman to lead a major military operation in the United States. She rescued more than 700 enslaved Americans during the Civil War’s Combahee Ferry Raid.

At a time when critics say the Trump Administration is erasing Black history at national museums and minimizing the contributions of Black Americans, particularly women, in seeking their own liberty, Dennard pushes the students to think more deeply about Tubman’s heroics, and what they mean now.

“I have to catch myself, because sometimes it turns into something personal when I am addressing these groups,” Dennard said. “And yet, look what she did. It doesn’t take a lot. Wouldn’t it be nice if we had one woman like Harriet in Congress right now? Just one!”

Dennard was 69 years old when the park’s manager, Dana Paterra, brought her out of retirement from the state prison system to put on a different uniform.

Paterra knew her because Dennard — along with Herschel Johnson, Donald Pinder, Valerie Manokey-Ross, and Addie Clash Travers — was always there to lobby for the park. Once, on Capitol Hill, a senator from Texas told the group that if they established a park to honor Tubman, he would retire. He did. Over time, the “Harriet on the Hill” advocates have died. Along with historian William Jarmon, she is one of the few left. Having her on the museum floor, Paterra said, instilled trust that the state and federal governments would get the story right.

“When we opened initially, there was a big influx of family members and descendants, and they were very emotional about the history,” Paterra said. “There were a lot of stories, and information, and a long process to digest.”

Kate Clifford Larson, the author of “Bound for the Promised Land: Harriett Tubman, Portrait of an American Hero,” also recalls Dennard softening tension during that fraught time.

“There was always back and forth with people in the Black community on the history and the truth. It was complicated, and it opened wounds, but finally, people who felt like they hadn’t been heard had their voices heard.” said Larson. “There were some people who were vocal, and not so nice. Mary was very nice. She had a mediating presence. She is all about inclusion. I’ve seen her in action and she is amazing.”

In those early days, Dennard worked with Angela Crenshaw, who would be promoted several times and is now director of the Maryland Park Service. The two connected as spiritual Black women interested in history, but Crenshaw said Dennard’s presence anchored the story.

Whereas Crenshaw grew up in Baltimore long after integration, Dennard experienced Jim Crow segregation on the Shore. She not only fought for the park, but was active in the Civil Rights Movement in Cambridge in the 1960s, even skipping school to march. She would have gotten away with it, too, she says, if not for the distinctive pleated dress she wore to school that day. Her mother caught a glimpse of it on the evening news.

“Miss Mary is to me, the beating hart of that park,” Crenshaw said. “She has the spirit of Harriet Tubman in her, and she takes that to work every single day. I love that Mary brings all of Mary to work all of the time.”

When the workday ends, her role as ambassador does not. Dennard has brought programs to the park on the history of the banjo as well as films about climate change in the region. She partnered with her classmate Gilbert Cephas, a descendant of Tubman confidant Jacob Jackson, to stage a Tubman musical. She’s worked with Renna McKinney, who is leading a group restoring Malone’s Church, where Tubman’s family worshipped, to protect the history and culture of the cemetery and structure.

“She always has a smile and she’ll say, ‘Renee, that’s a big task. If you need me to help you out, let me know,’” McKinney said. “She’s just a delight to be around. Some of that goodness can just rub off on a lot of people.”

Dennard doesn’t know how many more seasons she has. A two-time cancer survivor, she is finishing an African-American studies degree at Chesapeake College, where she is also on the board.

But, her colleagues say, the museum needs her. Dennard’s presence gives Crenshaw confidence that the state will never cave to pressure to remove any references to slavery, the Underground Railroad or escapes.

Keeping that history intact, Crenshaw said, “is a part of Miss Mary’s legacy. She gets that more than anyone else.”