The sister of New York Knicks shooting guard Reggie Bullock was shot and killed in Baltimore, five years after his first sister was fatally stabbed there, the heartbroken basketball player revealed on Wednesday.

"I never felt so BROKEN in my life!" the 28-year-old Bullock wrote on Instagram with a picture of his slain sister, Keiosha Moore. "My 2 queens, my 2 that go super HARD FOR ME!"

The 22-year-old Moore was brought by a civilian to Sinai Hospital in Baltimore just before 8 p.m. Monday with gunshot wounds to her chest, police said. She died at the hospital.

The distraught player said he wishes he could have done more to protect his sisters: "I failed as a brother to protect you from the harm of these streets. I FAILED TWICE, to be the TRUE BROTHERS KEEPER!"

Back in 2014, Bullock's transgender sister, 26-year-old Mia Henderson, was stabbed to death in an alley in West Baltimore. A suspect was arrested, but later acquitted at trial.

In the years since Henderson's death, Bullock has become one of the most outspoken LGBT advocates in professional sports.

"There's love in everyone's heart and you should just try to learn about a community before you try to downplay them," he told Vice Sports earlier this year.

Bullock, who grew up on Kinston, North Carolina, played college basketball at the University of North Carolina.

He's done stints with the Los Angeles Clippers, Detroit Pistons, Phoenix Suns and Los Angeles Lakers before signing with New York this summer.