My grandparents take my mother, my uncle and aunt, myself and my three cousins on vacation somewhere every year, so the rabbits in my family have frequently been sent to be bunny-sat somewhere other than our homes. My rabbit Humphrey has never been particularly stressed out by anything, and neither was his late bondmate Perry, and so I was only ever marginally nervous about them. They also lived with me through college and grad school, which meant that every year they got a new home, basically, and every summer lived with my mom and I– they were used to moving. However, my mom’s rabbit Monty is extremely easily stressed out and terrified of going anywhere in the car, so the first time we went on vacation with him we were very worried. However, he seemed to be reassured by Humphrey and Perry’s presence and has been totally fine every year we’ve gone– and I’m talking about a REALLY nervous bunny, here. So as long as you know he’ll be well cared for, isn’t too high strung, and has some reminders of home to keep him company, he’ll probably be fine.
If you’re really nervous and haven’t left yet, sleep with a baby-safe stuffed animal for a few nights before you leave, then give it to your bunny before he goes to your friend’s house. Then he’ll have something that smells like you while you’re gone. Anyway, have a good trip!