Warren Police Commissioner Jere Green says a fight broke out last night between the three people around 10 p.m. The brother and sister lived together in the 8100 block of Fisher Avenue, which is near the intersection of Eight Mile Road and Van Dyke Avenue.
Green says they were fighting over a parking space when the brother slapped his sister, which is said to have enraged the boyfriend. Green says the boyfriend then came at the 37-year-old brother with a long knife.
"Last night, we were under the impression there was two stab wounds, one to the back and one to the front," says Green. He explains when the medical examiner looked closer, though, it was discovered the knife had "entered the back, gone through the kidney and gone through the front."
The brother, who has been identified as Timothy Lamkin, was pronounced dead at St. John Hospital.
The 24-year-old boyfriend is in police custody and awaiting arraignment.
Other identities have not yet been released.