Rihanna: I'm Sad & Disappointed to Postpone Houston Concert!

Rihanna sucks on a lollipop while exiting Dan Deutsch Optical Outlook on Tuesday (April 16) in Beverly Hills, Calif.

The day before, the 25-year-old entertainer was forced to postpone her Houston concert after battling an unidentified illness.

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“I was sick since San Diego! I kept working because I thought two days off after the Vegas show would be enough time to recover and I f–ed up, those were two days off from hell and today is not different! I’m sad and disappointed about it! I had all kinds of plans for Houston!” Ri wrote on Instagram.