Janet Jackson by John Shearer/WireImage.com
Janet Jackson has postponed two concerts on her Rock Witchu tour due to illness.

The singer, 42, will be skipping over a scheduled Wednesday performance in Boston and a Thursday show in Philadelphia. She plans to return to the stage on Saturday North Carolina.

Jackson's postponements come after a short stay at Montreal's Royal Victoria Hospital. The singer was treated for two hours at the hospital Monday evening after falling " suddenly ill" shortly before her Montreal concert, a hospital spokesperson told the CBC News.

Jackson, 42, canceled the show and hopes to reschedule the stop on her tour.

No further details on her condition have been released. - Joyce Eng

Check out some of Jackson's music videos in our Online Video Guide.