Backstreet Boy star Howie Dorough is planning his sister's serenade.

Howie will honour the second anniversary of the death of his sister Caroline with two benefit performances, MTV reports.

Howie will perform in San Juan, Puerto Rico, on Sept. 13 and Buenos Aires, Argentina, on Sept. 15. Proceeds will go to the Caroline Dorough-Cochran Lupus Foundation.

The two concerts come after the Lupus 2000 benefit concert on June 25, which raised over $100,000 for the cause.

Caroline died of lupus on Sept. 12, 1998. The Backstreet star quickly established the non-profit organization that supports lupus research, education and gives financial assistance to people who have the disease but can't afford to treat it.

"This disease took my sister from my family," Howie said in a statement announcing the shows. "It means the world to me to have friends, family, and the public to help find a cure for lupus. Hopefully, in the near future, a cure will be found and no other family will have to endure such a tragic loss as our family has endured."

In more Backstreet news, the group plans to release their new album in November.

--AllPop