Kerwick is one of the few PPA employees who, instead of creative curse words, hears "thank you" and whose work can help restore people's faith in humanity.
"Sometimes, you can almost make a miracle come true for somebody," she said.
But it's not all sweet rides and good vibes. Kerwick also fields calls from those who've lost items. When she gets in Monday mornings, her voice mail, which holds 40 messages, is often full.
"On Monday mornings the people that are on the phone and the voice messages that are left at 2 and 3 o'clock in the morning, they're so drunk and out of their minds," she said. "I'm like, 'Did they even get out of a cab or did they lose themselves?' "
Sara Williams knows her husband was drunk on their wedding night last year when he left a paper bag in a taxi that was stuffed with thousands of dollars in cash the couple had received as wedding gifts.
"I called my husband every profanity in the book the day after our wedding. I didn't know if I could be married to someone who's stupid enough to leave a bag of money in the back of a taxi," Williams, 27, said. "I made him call my mother and tell her."
Meanwhile, Williams called the PPA. Since her husband paid with a credit card, the agency was able to give her the number of the cab, the name of the driver and even his phone number. She breathed, she called and she waited for an answer.
Given the GPS systems on city cabs, Kerwick is able to identify a taxi with the most basic of information: pick -up point, drop-off location and the approximate cab fare. The search becomes even easier if a person paid with a credit card or, especially, if they have a receipt.
"People are surprised," Kerwick said. "They call and say, 'I really don't have much information,' and I start asking them questions and they have more information than they think."
When Larry Deutsch, a lawyer from Penn Valley, left his backpack in a city taxi, he was impressed at how Kerwick was able to locate the driver.
"I had no idea of the extensive tracking system that the PPA has of the cabs," said Deutsch, 62. "I don't think people generally know that. It's a great, modern tool. I was blown away."
As a frequent cab rider, Deutsch said his experiences haven't always been positive, noting seat belts that don't work, cabbies who talk on the phone and drivers who grumble when he wants to pay with a credit card.
But when Kerwick was able to find his bag, he was so moved he wrote a thank-you letter to the PPA staff.
"I don't imagine they get a lot of compliments," he said.
People who are reunited with their lost cameras tend to be the most grateful, Kerwick said, but it was a woman and her missing candle that will stick with Kerwick forever.
The woman had visited Philadelphia on Mother's Day last year with her 12-year-old son, who was suffering from leukemia.
"His mother lost a box with a candle he had bought her and she called looking for it," Kerwick said. "And she kept calling me and she kept making me cry."
Kerwick didn't have the item, but she was eventually able to track it down.
"I wasn't giving up," she said. "That woman there with her dying child, it was the last thing he was giving her. It makes you human. It's not just another voice on the other end of the phone."
When Olea Daniels' 11-year-old son left his rented cello in a taxi last year, she never called the PPA. She called every cab company she could find in the Yellow Pages and not one of them ever mentioned the PPA's lost and found, she said.
That was pretty much in line with her prior experiences with taxis in Philly, Daniels said.
"I had a hate-hate relationship with Philly taxi drivers," she said. "It had always been my experience that they had very nasty attitudes."
This driver had been different, though. Daniels said they had talked like "old friends." But how could she find him? She didn't even catch the name of the cab company for which he worked.
Lawyers, newlyweds and children aren't the only people to leave items behind in cabs.
Kerwick said WMMR's midday disc jockey Pierre Robert once left a bag of "all different colored glasses" in a taxi. She was able to reunite him with his funky shades.
Eagles quarterback Nick Foles once came to the PPA office with his dad, Larry, who had lost his cellphone. Even though Larry Foles' phone was never found, the father and son were nothing but kind, PPA inspector Tom Nestel said.
"They were still really grateful," Nestel said. "They definitely weren't mad about it."
Dena Herrin wasn't mad when her mother left her recently deceased father's antique Vacheron Constantin watch in a cab.
She was heartbroken.
"The watch had been given to my father by my mother's father," she wrote to the Daily News in an email. "My father wanted it to go to my husband. The sentimental value was much more important than the financial."
Herrin wrote to the PPA and received what appeared to be an automated email response. She said nobody ever followed up.
"I don't think any effort was made to help us," she said.
Kerwick receives about 20 items a week from cabbies who turn them in, and at least two times as many people contact her about missing items each week.
The most common items lost are cellphones. If one is turned in, Kerwick finds a cord to charge it with, then she tries to find out who the phone belongs to by looking for "mom, dad, husband or wife" in the contacts.
Phones that aren't claimed after 90 days are sent to Cell Phones for Soldiers, a nonprofit that provides free communication to soldiers overseas.
While iPhones are the most common items lost, the most unusual item that ever went missing in a cab was an actual eye, well, a glass eye to be more precise. Kerwick said a man called her looking for his glass eye but she was unable to locate it. The eye was never seen again.
Aisha Loeks, 27, of Philadelphia, left behind her Teenage Mutant Ninja Turtles bo staff in a taxi last year.
Loeks created Teenage Mutant Ninja Turtles costumes for her and her friends last Halloween. As Donatello, she was armed with a bo staff, which she forgot in a cab at the end of the night.
"I literally knew it the second after it happened," Loeks said. "I even yelled and ran after the cab."
Loeks contacted the PPA, hoping such an unusual item would be turned in.
She also posted about the bo staff on an online message board at lf.taxi.philadelphiapa.tel.
Although many people who post on the site appear to believe they are contacting cab companies or the PPA, they are not. The site is administered by a man named Mikhail Lobachev who lives about 5,000 miles away - in Dubna, Russia, near Moscow.
"Several years ago, when a new domain zone - .tel - was opened, I registered the Philadelphia.tel domain name and started to learn how to make a site," Lobachev, 53, wrote in an email to the Daily News. "Then I had an idea: I could make a message board about lost and found."
There are hundreds of posts from people on Lobachev's site dating back to 2013 - people looking for their passports, their high heels, their books on love and their books on Virgil.
The posts range from the heartbreaking ("a small pink coin purse with a pair of earrings inside. They were from my mother who died of cancer recently") to the seemingly absurd ("There were three of us in the cab, a guy, a monk and a nun").
PPA administrators were not aware of Lobachev's site. Lobachev said he has received thank-you messages from those who have been reunited with their items thanks to his site.
The Daily News randomly contacted 15 people who had posted on Lobachev's site. Of the six who responded, two said they were reunited with their items, one with the help of the PPA staff. The other four, all of whom said they did contact the PPA, said their items were never found.
The items could have been picked up by the cab's next fare or, in some instances, by the driver.
Kerwick said it tends to be the same cabdrivers who turn lost items over to her again and again.
"Some of them, I guess with their religion, if it's not theirs, they can't keep it," she said. "And some, you never see."
Herrin said she never saw her father's antique watch again and Loeks was never reunited with her bo staff.
"The Ninja Turtle costume is incomplete now," Loeks said. "It's just a turtle costume now."
But Daniels, whose son left his cello in a cab, had a different experience. When her cabbie realized what had happened, he dropped the cello off at her son's school on his own accord. He didn't leave his name or number, so Daniels never got to thank the man.
"I think the real story [is] in the kindness of the taxi driver," Daniels said. "I gave up looking for him but to this day it still warms my heart he remembered where the school was and returned the cello."
And remember Sara Williams, whose new husband left thousands of dollars in wedding-gift cash in a taxi? The PPA was able to track down the driver of the cab and gave Williams his phone number.
The cabbie said he did have the bag of wedding envelopes and gave Williams and her husband his address. Williams said the driver lived in a tiny apartment with his family. He didn't take a single dollar from the envelopes.
The young couple tried to give the cabbie a couple hundred dollars as a reward, but he refused, so they placed it on his table.
"The driver was a beautiful man," said Williams, who now lives in L.A. "Philadelphia will always be near and dear to my heart, so it was great to realize there are really great people there."
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