Boston Marathon bombing survivor Erika Brannock has had an astonishing 7-month journey, from having more than a dozen operations to returning to the classroom to walking across the finish line at a 5K race. (Kevin Richardson/Baltimore Sun video)

CHARLOTTE, N.C. — With her wheelchair pushed aside, Erika Brannock gripped her walker and moved slowly toward the Thunder Road 5K finish line.

Inside, her brother-in-law, Michael Gross, was bursting with pride to see Brannock walking with a prosthesis just seven months after the Boston Marathon bombing left the Towson preschool teacher gravely injured and her left leg amputated above the knee.

But rather than focus on the seriousness of the moment, Gross asked Brannock, "Can you pick up the pace?"

"We were joking around the whole time," said Brannock, 29. "Laughter has always been the best medicine for me. Taking such an emotional moment and being able to then have fun with it at the same time helps a lot."

Levity has been key for the family in overcoming the physical and emotional challenges since the bombing that also injured Brannock's sister, Nicole Gross, 32, a fitness instructor from Charlotte who suffered broken bones, a nearly severed Achilles tendon and other injuries.

The three were waiting near the finish line at the Boston Marathon on April 15 for the women's mother, Carol Downing of Monkton, to complete the race. Michael Gross, 33, suffered burns and lacerations from the explosion.

Saturday was the first time Brannock, Downing and the Grosses had been together at a race since the Boston bombing. Downing ran the half-marathon while the others participated in the 5K.

The experience for Brannock was a symbolic milestone, she said.

"It united us all together again and expressed to ourselves and to everyone else that we're not afraid to be back at the finish line," she said. "It was the longest I've walked so far."

Bre Dickerson of Souderton, Pa., Brannock's friend from college, pushed her in her wheelchair for most of the 3.1-mile race. But once she was within roughly a 100 feet of the finish line, Brannock stood up and walked across it.

Brannock received her prosthetic leg about a month ago after undergoing approximately a dozen surgeries and spending 50 days in a Boston hospital.

Watching Brannock cross the finish line was a testament to her "character and determination," Dickerson said. The strides Brannock has made are "really just incredible. There is no other way to describe it," she said.

After Brannock and the others completed the 5K, they waited with about a dozen family members and friends to watch Downing finish her race.

Downing said the run was emotional at times, but the event was a chance to celebrate "how far we've come."

"It was just a good feeling knowing that they were back at the finish line, waiting for me," she said. "I knew they were going to be safe."

Nicole Gross, who served as the race starter on Saturday, said cheering from the sidelines felt comfortable. She ran the Thunder Road Half Marathon last year, and over the years helped many runners train for the race.

"I felt like myself again," she said.

Her recovery has been difficult, Gross said, but she's persevered by tapping her "inner athlete." Gross was a standout athlete as a student at Mount Hebron High School. She went on to swim competitively in college at the University of Tennessee.

Before she dropped the green flag to signal the start of the Thunder Road festivities earlier Saturday, Gross said to the runners, "I want to say, 'Best of luck to all of you.' Whatever the reason is that you're running today, be brave, stay positive and be Boston strong every mile of the way."

Race organizers donated $13,000 to the Be Strong Stay Strong Fund, which was established to help Brannock and the Grosses with their medical bills.

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