In 1965, Bernyce Mills-DeVaughn sat crossed-legged at the entrance to the 30th Street post office with three other women. They were protesting “unfair hiring practices,” Mills-DeVaughn says. At the time, Black people were not considered for leadership roles.

With their elbows interlocked, the women sang: “Just like a tree planted by the water, we shall not be moved.” And after a while, they were warned that the police would be called if they did not vacate. The women kept singing.

As police officers placed handcuffs around their wrists and drove them to the police station at Eighth and Race, they continued to sing. Because they were teenagers, prominent activist Cecil B. Moore had advised against a sit-in, “but we did it anyway because we were freedom-fighting,” Mills-DeVaughn says now.

After closing in March because of pandemic restrictions, Harriett’s Bookshop in Fishtown will be reopening Monday at 4 p.m. with its own version of a sit-in demonstration — a response to the racist and threatening emails that were sent to several Philly Black-owned businesses in September.

And Mills-DeVaughn will be there, continuing the legacy of peaceful demonstrations in Philadelphia.

“We’re calling it Protect or Serve: Harriett’s Sisterhood Sit-In,” says Jeannine A. Cook, the bookshop’s owner. “In my mind, it’s a modern-day sit-in.”

The event, sponsored by New Kensington Community Development Corporation, will take place at 1108 Frankford Ave., just around the corner from the shop. Participants will sit, socially distanced, to hear musical performances by local musicians, including jazz singer Laurin Talese, and there will be discussions led by attorney Michael Coard, Philadelphia poet laureate Trapeta B. Mayson, author and motivational speaker Wallo267, and the Colored Girls Museum founder Vashti Dubois, among others.

Cook said the first 50 people who arrive at the event will receive a copy of Caste: The Origins of Our Discontents, a new book by Isabel Wilkerson. “In that book, [Wilkerson] is talking a lot about how to break down barriers through dialogue. You’ll see elements from the book all throughout the evening.”

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When news of the racist emails spread, “people were like, ‘Call the police,’ but that relationship is so sordid, especially in the neighborhood where I am,” said Cook. “We need more strategies on how to protect and serve one another as neighbors, as opposed to consistently trying to outsource that responsibility.”

Soon after the emails, Cook’s older sister, Jasmaine, traveled from New York to Philadelphia to support her. “Even if it wasn’t a physical threat, [Jeannine] has to know I’m here for her,” said Jasmaine Cook, who co-organized the event. “We have a lean-and-let-lean philosophy between us.” And that philosophy is one of the event’s guiding principles.

“The event is really about dialogue,” Jeannine Cook said. “We’re going to be teaching some specific skills around protecting one another and serving one another,” such as conflict deescalation. “Can we ask better questions of one another as opposed to making demands?”

Mayson said she’ll focus her discussion on the importance of mental well-being.

“The theme of the event is ‘protect and serve,’ but that also involves protecting your mind and spirit,” Mayson said. “With the heavy work that a lot of us are doing in the community — whether it’s through your art or practice, or physically out in the street protesting and demonstrating — you also have to be centered and well.”

Mayson’s discussion is inspired by a poem by the Jamaican American poet June Jordan, “We Are the Ones We Have Been Waiting For.” “We need to be the owners of our own healing,” Mayson said.

Regina Colantonio of Ardmore learned about Harriett’s on Instagram. And when she and her husband drove past the shop earlier in the summer, she made him pull over. She purchased a copy of White Fragility by Robin DiAngelo and Stamped From the Beginning: The Definitive History of Racist Ideas in America by Ibram X. Kendi.

She’ll be at the event on Monday because “I want to show up physically, mentally, emotionally in spaces where Black women are telling their stories.”

Mills-DeVaughn said she’ll be honored to be in attendance.

“On its own, the demonstration won’t solve issues. The courts solve issues,” she said. “A lot of times, when we marched [in the 1960s], there were only two or three people out there. The demonstration sheds light on whatever issues are going on, and that’s what’s important.”

» READ MORE: Harriett’s Bookshop in Fishtown: 'A space of peace for people in a chaotic world’