Lisa Styles was the ideal mother, a woman who gathered up her three young kids for picnic lunches in the park and who built her life around them.

Late Monday morning, she had strapped her 3-year-old son and 1-year-old daughter into a double running stroller and gone for a run on Washington Road when an SUV struck her and the stroller, fatally injuring her and knocking the stroller sideways into the street.

Ms. Styles, 36, of Mt. Lebanon, was rushed to UPMC Mercy where she underwent surgery for a severe head injury. She was pronounced dead at 1:27 p.m. Tuesday at the hospital, according to the Allegheny County medical examiner's office.

The children, whose names were not released, were treated at Children's Hospital of Pittsburgh of UPMC.

Benjamin Cope (2007)

Mt. Lebanon police say the man behind the wheel of the 2003 Toyota 4Runner, 20-year-old Benjamin T. Cope, now faces charges of driving while impaired and driving while under the influence of a controlled substance. Police said they believe he was high on marijuana. Mr. Cope, of Mt. Lebanon, likely will face additional charges after police confer with the district attorney's office, Lt. Lauth said.

Police said the SUV failed to stop at a stop sign as Mr. Cope turned right onto Washington Road from Beadling when Ms. Styles was struck around noon on Monday.

Records indicate that Mr. Cope has paid $755 in fines to Mt. Lebanon, South Fayette and Pittsburgh since February 2006 for traffic violations, including speeding, disregarding a traffic control device and driving without a license.

Karly Tetlow, who met Ms. Styles when their oldest daughters shared a Gymboree class, said she often took her children out for walks. Occasionally, she would stop into Ms. Tetlow's clothing boutique on Washington Road with her children.

"What I know of her is that she was a very active ... really involved with her kids," she said. "They were with her all of the time."

The last time they spoke, Ms. Styles told her she was remodeling her family's home on Sunnyhill Drive that she and her husband had recently purchased. And she had packed a lunch in the car and was taking her three children for a picnic in the park.

"I just can't imagine the loss that they're going to feel," she said. "It's horrific, just horrific."

Ms. Tetlow said she occasionally walks that stretch of Washington Road with her own children. The intersection where Ms. Styles was struck can be dangerous, because drivers frequently pull out past the stop sign at Beadling Road before turning onto Washington Road.

She worries because schoolchildren often walk down Beadling Road to get to Markham Elementary School.

She said that now she'll be extra vigilant while walking with her children.

"We are a walking community and you assume that you're safe and then something like this happens," she said. "I will absolutely be much more cognizant you know every time I have to cross a street."

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