RALEIGH, N.C. — A year to the day after his death, a Raleigh church group held a vigil Sunday for murdered UNC researcher Eric Miller.

Miller, who worked at the Lineberger Comprehensive Cancer Center in Chapel Hill, died last year from arsenic poisoning. His sister came all the way from Kentucky to participate in the vigil. Participants hope it will help keep the unsolved case in the public eye.

"Our parents now carry a heavy burden, a deeply saddened heart. And the reality that they will never see their son again is often too much to bear," said Pam Baltzell, Miller's sister.

Investigators found an arsenic compound in the labs of his wife, Ann Miller, and her supervisor, Derril Willard, at Glaxo Smith Kline. Police say Miller gave them one interview, but has not talked with them since.

Willard committed suicide after warrants revealed he had a relationship with Miller.