Was I wrong to tell gramma?

My cousin went to the prom and my gramma who is 83 said I wish I could have seen her in her pretty dress. The next day the pictures were in the newspaper so I called gramma and told her. Yesterday, at Burger King I seen my cousin and my aunt and my cousin asked why I told gramma. I said I didn't need to tell her- it was in the paper. She got really mad and cussed at me. Was I in the wrong to tell gramma? What should I do--apologize??