Katy Perry scenario

You are planning a special 21st birthday party for January 14, for your sister. Knowing that she loves the music of Katy Perry, you are thrilled that you were able to hire Katy Perry to perform at your sister's party! Wow! You knew this would be a perfect party!

The performance fee for the party was quoted as $10,000 for one hour of entertainment. You decided this was a fair price and well within your budget for the party. You have agreed to pay 50% of the performance fee at least 30 days prior to the performance date and the remaining 50% when Katy Perry shows up for the party.

Unfortunately, last week the agent for Katy Perry contacted you to say that she was erroneously double-booked for your date and that she will be unable to perform at your sister's party. He is very sorry about this and he hopes that you will understand. You try everything you can to make him change his mind, but it is clear to you that Katy Perry will not be coming to your sister's party.

You have not made any payment for the performance, since your first payment will not be due for another several days. You believe that this circumstance is a breach of contract and you filed a lawsuit against Katy Perry, seeking a ruling from a judge ordering that Katy Perry perform at the party and fulfill the terms of your contract. Alternatively, you want the maximum amount of damages you can obtain from the defendant. Now, you must plan the presentation you will make to the judge at your court hearing.

Consider again the Katy Perry scenario (written above) Assume that you decide that you do not want to pursue the matter, but your sister disagrees.  On what legal basis might your sister file a lawsuit against Katy Perry for breach of contract?  What kind of argument would she need to make about her status in the original contract between you and Katy Perry? (Remember, your sister is not a party to the contract between you and Katy Perry, but it does state that the performance is for your sister's birthday party.)