Freedom High School senior Kiera Pheiffer in February told her parents she was going to walk at her June graduation.

At the time Pheiffer, 17, hadn't even sat up since she was seriously injured in a car crash in October.

Four months later, Pheiffer achieved her goal, as she surprised classmates by walking across the stage with the assistance of a walker and two aides during Freedom's Thursday night graduation.

"I've always said ... I was going to walk at graduation," Pheiffer said in quiet, labored speech Thursday. "I'm feeling very happy and excited."

As she crossed the stage in her walker covered in black-and-gold streamers, the entire crowd gathered at Stabler Arena in Bethlehem rose to their feet and gave her an extended standing ovation.

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Pheiffer's parents, Bill and Helene, said they had some doubts when Kiera declared her goal of walking at graduation. But every day, she asked to practice walking so she could cross the stage Thursday.

She's only been walking with a harness-assisted walker for two months and a regular walker for a month, Helene Pheiffer said.

"She's a very determined girl," Helene Pheiffer said. "Kiera is very goal oriented, and her therapist encouraged her to have goals."

Since three weeks after her Oct. 4 car crash, Pheiffer has been a patient at Good Shepherd Pediatric Unit in Bethlehem. Good Shepherd Physical Therapist Sarah Barnabas and Recreational Therapist Julianne Hirst helped Pheiffer across the stage Thursday.

"Our staff is delighted to have been able to help make this day a special one for Kiera," Carissa Snelling, Good Shepherd's Pediatric Unit therapy supervisor, said in a statement. "She has not seen many of her classmates since the accident and was eager to surprise them at graduation and show them her progress."

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Several of Pheiffer's close friends have visited her at Good Shepherd, including her best friends twins Ally and Kelly McCready, who visited her almost every day, Helene Pheiffer said.

"Pretty much no one knows I'm here," Kiera Pheiffer said with a smile, as she waited backstage before the ceremony, resting in a wheelchair.

Pheiffer suffered a traumatic brain injury during the car crash, which occurred not far from her Bethlehem Township home on Farmersville Road while she was on her way to work. Her left side is especially weak due to her brain injury and her recovery has been slow, Helene Pheiffer said.

Pheiffer's next goal is going home. She's been giving a tentative release date of June 26, and she's counting the days. She had set another goal of being home by her 18th birthday on July 8.

Her family is unsure if they'll have a large welcome home or birthday party because Pheiffer sometimes gets overstimulated. But her father said they'll both be very special days either way.

"We pretty much celebrate every day she's still here," Bill Pheiffer said.

The Freedom Family has rallied around Pheiffer since her injury, including holding a large vigil at the school and raising almost $42,000 to help in her care.

Lynn Olanoff can be reached at lolanoff@lehighvalleylive.com. Follow her on Twitter @LynnOlanoff. Find Bethlehem news on Facebook.