Discussions

My 13 year old daughter and her close friend, share the same birthday. They also have the same group of friends. A couple of weeks ago, my daughter mentioned to her friend that she was planning on having a sleepover this Saturday for her birthday. The friend said she was also planning on having her party Saturday. We then decided we would have her sleepover Friday even though it was an inconvenient day just so friends weren't having to choose and no one's feelings were getting hurt. The friend came back and said that her mom had changed her mind and that they would be having her party on another weekend. We went back to our original plan of this Saturday.  
 
Find out yesterday that they changed their minds and are having her party tomorrow as well. Both girls invited the same group of people. Someone's feelings are going to get hurt.  
 
I am a little aggravated and I am debating whether to say something or not. They were aware of our plan because the daughter was sent an invite. I wouldn't care other than they invited the exact same people and now, some of my daughter's friends are not coming. Her feelings are hurt. The other child is also having a second party next weekend.  
 
Would you be ticked and would you say something to the other parents?