PEABODY-Cab driver Ryan Gilbert said in an interview he fought off four people who robbed him at knifepoint Friday because, “I wasn’t going to lose my family.”Gilbert, 27, a Peabody resident and employee of Community Taxi of Peabody, said he was on the phone with his girlfriend Dianne, who is the mother of their 6-month-old daughter Emma, when four teenagers from Peabody and Lynn robbed him on Sabino Farm Road about 11:55 p.m.”They put a knife against my throat,” Gilbert said. “When I felt it, I fought back and the kid in the passenger seat kept punching me in the face.”The suspects jumped out of the taxi with Gilbert’s cell phone but no cash. One suspect dropped the weapon, a butter knife, next to the car and Gilbert tried to give chase.Dianne says she became horrified because she was in the middle of talking to Ryan when he got robbed.”I heard the buttons pushed and the phone hang up,” she said.After trying to call Ryan back and getting no answer she immediately called friend and fellow cabbie Marco Aleixo. Ryan had told Diane his location prior to the robbery because he thought his customers were “sketchy people,” she said.”He (Marco) was down there within seconds and had me on the phone, letting me know everything was OK,” Dianne said.Friday wasn’t the first time Gilbert was robbed while driving a cab: It was his third.At six feet tall and 260 pounds he says, “I don’t know why I keep getting robbed.”About a month ago, a fare from Peabody pulled a gun on him when he exited the taxi in Charlestown, he said.In a separate robbery three years ago, he said a Peabody man, “got a whopping $45 and is doing 12 years in prison.”Police arrested four suspects in Friday’s incident and identified them as Robert Downing, 18, of 9 Sabino Farm Road, Peabody, Ryan Wilson, 17, of 605 Lowell St., Peabody, Michael Castaldo, 18, of 143R Washington St., Peabody and a 15-year-old girl of 50 Newhall St., Lynn. All four face armed robbery and assault charges.According to a press release from the Peabody Police Department, the female was found almost immediately after police arrived.K-9 units from Peabody and Danvers later found Castaldo hiding in a backyard tool shed on Loris Road. According to a police log, Castaldo was charged with mistreating a police dog and marijuana possession in addition to robbery.Police continued to search for approximately two hours until they found the remaining suspects, Downing and Wilson, walking along Tammie Lane where they were arrested.