An ex-con who allegedly killed a Brooklyn grandmother with a stray bullet should rot in jail, her family said.

“I didn’t think they were ever going to catch this guy,” said Michael Surman, the grandson of victim Anna Surman, 87. “I hope he spends the rest of his life in jail.”

Malcolm Mitchell, 26, was busted Friday and charged with murder for Surman’s Aug. 2, 2009 death, police said yesterday. The elderly woman was shot in the neck as she fed stray cats.