sleep-over...

my 3 yrs old kiddo is having her 1st ever sleep-over at her cousin's place tonite ..she was so so so excited....sincerely, am wondering should we "camp out" in the car in the carpark tonite? just in case she needed us or what if she get homesick?? oh gosh! i need to pack extra diapers for her too, where's the diapers!!!!.... oh gosh!!! am so worried...but she was so so excited... :(