How to convince my mom.... PLEASE HELP...?

My mom is hard to convince but it IS possible. My birthday is in 10 days and I was going to a hotel with a bunch of my friends. For one of my previous birthdays I went to a beach and stayed in a beach house, it was so much fun and so I want ot go again. How can I convince my mom to let me bring one of my friends who she knows her parents and her. She said it is too far to bring a friend (1 hour drive). Should I stick with three friends and a birthday in a hotel or try and convince her to let me bring a friend to the beach with me. I would rather go to the beach but I would rather have a friedn there instead of a pestering little brother. How can I convince her to bring my friend.. I have 1 day!!