When Pink tweeted a photo of herself in the hospital, hooked up to an IV but flashing a smile, she neglected to share the reason that she was admitted and seeking treatment other than "stomach flu." Now, a different reason for her hospitalization has surfaced.

Pink apparently had her gallbladder removed, according to Life & Style.

A friend of the singer told the magazine, "At first she had these bad stomach pains and didn't know what it was, and then it got really bad. They realized she needed to have her gallbladder taken out, so she did!"

The gallbladder issue meant that Pink had to cancel a planned performance at an LGBT fundraiser for President Obama in L.A. on June 6 and that she had to celebrate daughter Willow Sage's first birthday while in the hospital.

The singer did seem a little bummed about how her medical problem messed with her plans to celebrate with her baby girl and to perform at a benefit for the leader of the free world.

Check out Pink's tweets on the matter below. We hope she is feeling better and on the road to recovery, even if she had to rearrange her schedule a bit. Health first, Pink.

Watch the Pink 'Raise Your Glass' Video

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