dear Sarah，I am terribly sorry to tell you that I am unable to attend your birthday partnet Thursday evening. That is owing to the fact that my younger brothersuddenly fell ill and was taken to a hospital this morning. I have to go thereimmediately and take care of him. As told by the doctor in charge, it will takearound five days for him to recover and I have asked my boss for a really regret that I cannot go to celebrate your birthday personally andwould miss the perfect chance of enjoying myself with all our old friends. Ihave chosen a small gift for you and will send it to you tomorrow to show mybest wishes. Besides, please give my regards to our friends when you meet themat the party.
Cordially,