The 300 toothbrushes proved too much for Margaret Dimond.

She stopped what she was doing: sorting through heaps of donated supplies meant for migrant families detained at the U.S.-Mexico border. Standing in a friend’s living room in Potomac, Md., Dimond lifted the lumpy plastic bag above her head and launched into a “happy dance.”

“Wow!” she exclaimed, when she finished pumping her arms, shaking her head and stomping her feet. “Doesn’t that make you want to cry? Three hundred toothbrushes at one go!”

The half-dozen women around her smiled and laughed — but then all of them quickly got back to work. For good reason: They faced mountains of diapers, fluffy gray towels, multicolored bedsheets, even a small mound of Kleenex packets.

The team of volunteers carefully organized the items: backpacks by the staircase, face wipes on the couch, toothpaste near the piano. They helped Dimond, 53, and Jordana Carmel, 55, load the haul into both of their cars so the two women could take it to a rented storage unit in nearby Kensington.

Soon, Dimond and Carmel would take a much longer drive. In early August, they packed all they’d gathered into a rented truck and drove 20 hours to Laredo, Texas. They gave the supplies to Catholic Charities of the Diocese of Laredo, which will distribute them to individuals and families released from U.S. Customs and Border Protection detention facilities.

Congress approved a $4.6 billion border aid package in June meant to improve poor conditions at detention centers, which government watchdog groups have decried as overcrowded and unsanitary. Several children have died in federal custody at the border over the past year.

“Our hope is to provide the necessities to help these people feel human again,” Dimond said.

She came up with the idea at 1 a.m. earlier this summer. Dimond, who works out of her Rockville, Md., home as an internet and technology consultant, had just wrapped up the day’s assignments. She was about to fall asleep when she spotted a New York Times headline on her iPad: “ ‘There Is a Stench:’ Soiled Clothes and No Baths for Migrant Children at a Texas Center.”

The word “stench” was arresting.

“So I read the article, and beyond the thought of the horrible conditions, I just thought, ‘This is so solvable!’ ” Dimond said. “There’s a need that can be met. I know the private sector — small businesses, individuals — can meet that need.”

It was too late to do anything that night. So Dimond set her alarm for 6 a.m. and — after imbibing “significant amounts” of coffee — sketched out an action plan in brown ink on a white legal pad. Her mission was clear: Deliver toiletries, clothes and other hygiene items to incarcerated migrant families and children. But how?

First up, research and outreach. Over the next few weeks, Dimond read everything related to detention centers that she could find online — especially useful, she said, were small Texas-based news outlets. She also contacted lawyers and nonprofit organizations working along the border to discuss what was needed and what was possible.

Soon, Dimond began zeroing in on Catholic Charities-Diocese of Laredo (CCDOL). Benjamin de la Garza, executive director of the nonprofit social services agency, said CCDOL has seen about 70 people exiting detention centers every day over the past month, though the number can sometimes rise above 200. Border Patrol agents direct families approved for release to the Catholic Charities shelter, where staff members care for them and help them find a place to stay as they await hearings in immigration court.

“These people come to us in need of showers, in need of personal hygiene, in need of clothes, in need of food — they even have medical needs sometimes,” de la Garza said.

He added that efforts such as Dimond’s are vital: “Without donations and support from all over the U.S., it would be very hard for us to sustain this crisis,” he said.

As she gained a clearer understanding of the situation at the border, Dimond — drawing on her background in coding — whipped up a website detailing her project. She also reached out to family, friends, current and former clients, people from past professional lives — anyone and everyone she thought might be able to help. Everybody was more than willing to pitch in, often by donating items such as shampoo and hairbrushes.

One of the people she contacted was Jordana Carmel, a longtime friend and her former yoga instructor.

Carmel, who works as a life and health coach and massage therapist in addition to teaching yoga, was feeling “deeply depressed” by news reports about the detention centers, she said. She often sat in her car and wept as she listened to radio updates from the border. The dilemma made Carmel think of her 100-year-old grandmother, a Holocaust survivor, who immigrated to the United States from Germany during World War II.

“We must all remember where we came from,” Carmel said. “None of us are that far removed from the moment of immigration.”

Carmel, who wanted to help migrant families but had no idea how, was thrilled to hear from Dimond. She signed on to co-lead the project almost immediately.

“Well, actually, I just didn’t give her a choice,” Carmel said. “It became a ‘we’ without us ever discussing it.”

Around the same time Dimond and Carmel joined forces, the two women also connected with KindWorks, a Maryland-based nonprofit organization that collaborates with other organizations and government agencies to engage Washington residents in community service. Carmel found Deb Lang, the executive director of KindWorks, through a former massage client. With that, the twosome morphed into a trio. Once they started using KindWorks’ web of contacts and resources — and publicizing their collection effort on social media and over neighborhood e-mail lists — the three women found themselves deluged with supplies, offers of help and money.

“That’s what KindWorks does — we take someone with an idea like Margaret and we blow it up,” said Lang, who hosted a recent sorting party at her Potomac home. It was the second such gathering that KindWorks has held.

“We could not have done this without KindWorks,” Carmel said. “Deb has been amazing.”

Dimond, Carmel and Lang set up collection sites in homes, churches and synagogues across the region. After consulting, in part, with CCDOL, the three women published a catalog of the items most useful to migrants, including shoelaces, water bottles, deodorant and baby formula.

They also rented a storage unit. Until then, Dimond had kept the supplies in her home. The rows of shampoo and stacks of blankets remained there until Aug. 8, when Dimond and Carmel embarked on their road trip.

In addition to Laredo, the women visited the Texas cities of McAllen and Brownsville. All costs were covered by donations.

Both women have driven trucks before, so neither were nervous, they said. Nor do they feel so hopeless when they read news from the border anymore. Instead, Dimond, Carmel and Lang wake up most mornings feeling “amazed” and “inspired” by D.C. area residents’ “overwhelming response” to their project, Carmel said.

One such resident is Mariam Afzal, 37, who drove from her home in McLean, Va., to drop off a car’s worth of supplies at Lang’s house. Afzal’s family immigrated to the United States as refugees from war-torn Afghanistan when she was 9 months old.

“It is a very personal thing to be able to help with this,” Afzal said, pointing to her refugee status. “But no matter who you are, all human beings should have dignity.”

She shrugged. “That’s really all there is to it.”