Grande, whose showbiz family also includes pop-singer sister Ariana Grande, was previously announced to appear in the Off-Broadway return of Pageant, which begins June 29, but is unable to participate in the production due to his involvement with "Big Brother." New casting was announced June 19.
The reality series, in which contestants compete to stay within the "Big Brother" house the longest, premieres June 25.
Grande revealed to People Magazine that he will not be using his recognizable last name and will instead go by his father's last name of Marchione. "If I get recognized, I'm going to have to win Head of Household and do damage control. If I don't, I plan on flying under the radar the first few weeks," he said.