PT-125 was an 80-foot Elco motor torpedo boat, built at the Elco works in Bayonne. She was laid down on 9 May 1942, launched on 6 August, and placed in service on 22 August. She went to Motor Torpedo Boat Squadron 6. Men called her Willie's Headache.
On the morning of 22 August 1943 C. Murray had her on a daylight run from Lever Harbor toward Kolombangara, with air cover. She and PT-108 started into Webster Cove at 0730. PT-124 stayed outside to cover the entrance. Shore machine guns hit the boats that went in. The men killed in that cove that morning, and the man who took the wheel, were on PT-108.
On 4 September Japanese planes damaged her off Meresu Cove, on the west side of Kolombangara. In October, on patrol with PT-124, two Japanese men in a canoe between Kolombangara and Choiseul were shot when they resisted being taken.
On 29 May 1944 Squadron 6 was broken up and she moved to Squadron 10. She was not lost in a fight. On 11 November 1945 U.S. forces stripped her and destroyed her at Samar.