Flowers are left at the scene on Tuesday where Jennifer Lawson was fatally struck by a dump truck a day earlier in Arlington. (Matt Zapotosky/The Washington Post)

To her friends, Jennifer Lawson was an Arlington everymom — a supermom, really — who poured what seemed like an endless store of energy into raising her three kids.

She took them on vacations, volunteered at her oldest child’s school, and even sometimes popped back in to the public affairs office where she used to work so she could show off her beloved trio.

“They were everything to her,” said John Schmidt, a friend and former co-worker.

It was no surprise, then, that even as she died, Lawson was doing something motherly.

According to police, friends and witnesses, Lawson, 39, had just loaded her daughter into a car seat in her minivan when a dump truck pulled up. It hit Lawson and the door of her minivan with such force that witnesses say the van’s door remained stuck to the truck’s side.

Jennifer Lawson (Courtesy of Deanna Angello)

On North Little Falls Road, in front of the Arlington County elementary school where Lawson’s elder son attends kindergarten, she was left fatally injured in the street. Her daughter was not hurt, police said.

“To think that this could happen so instantaneously, so unexpectedly,” said Sue Meehan, who saw the aftermath of the crash Monday, “it’s just very tragic.”

A day after Lawson’s death, her friends said they were grieving and struggling to process what had happened, as police and prosecutors worked to reconstruct the crash and determine who — if anyone — was to blame.

As of Tuesday afternoon, no one had been cited or charged. Officials at Nottingham Elementary School sent home a letter to parents with children in the same class as Lawson’s 5-year-old son telling them what had happened and asking for their help in “fostering a safe environment” for the boy to grieve.

Lawson, police said, had parked her minivan in the 5900 block of North Little Falls Road so that the driver’s side opened to traffic. Such a practice would not be unusual: White lines on the street designate an area for cars to park.

The street, though, is not especially wide, and someone stepping out of a vehicle on the driver’s side would probably be emerging into a lane of traffic. Police said they were still investigating where Lawson was standing when she was hit and whether the minivan’s door protruded over the parking space line. They said they were also investigating how fast the truck was going.

What is clear is that about 11:30 a.m., the dump truck hit Lawson and the back driver’s-side door of her minvan, police said. Michael Meehan, who was watching his grandchildren at a home on the street, said he heard the impact of metal on metal and soon saw Lawson in the road, her leg “mangled” by the collision.

Michael Meehan, Sue Meehan’s husband, said others had already rushed to attend to Lawson. He said the dump truck stopped, and the driver stayed at the scene.

On Tuesday, friends and acquaintances attached flowers to a utility pole at the scene of the crash. Friends said they assumed that Lawson was at the school to pick up a child, although she also sometimes went there to volunteer.

Friends remembered Lawson foremost as a loving wife and doting mother to three children — a 5-year-old son, a 4-year-old son and a 2-year-old daughter. John Schmidt said Lawson had worked at his public affairs firm until she left about the time her first child was born.

Although she wanted to be a “full-time mom,” Lawson sometimes brought the kids back to the office for lunches, Schmidt said.

“This thing just really struck a chord with people,” Schmidt said of Lawson’s death. “How a family can be disrupted so quickly, it’s just tragic.”

Deanna Angello, one of Lawson’s best friends, said Lawson went out of her way to ensure that she spent enough time with each child, sometimes doing something as simple as taking them to Starbucks for a cookie.

“They adored their mother,” Angello said. “She made each of them feel special.”

Schmidt said Lawson and her husband would take vacations with the kids — and by themselves — to places such as the Bahamas and Costa Rica. Leigh Ann Bradley, another friend, said Lawson competed in races and was known for ordering the most nutritious item on the menu when she went out with a group for lunch.

“It’s just such a senseless tragedy,” Bradley said. “I’m just in total shock.”

Dan Regard, a family spokesman, said Lawson’s husband was too grief-stricken to be interviewed. He said Lawson was a “committed mother and homemaker who lived for her children and her love of running.”

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