First sleepover...

My husband and I are going out to a work event for him on Saturday and we won’t be late. My parents are watching the baby - 5 weeks old - and my mom has offered to let him sleepover. My husband doesn’t want him to stay over and he wants him to come home when we get back. I kind of want the night off while it’s on the table to get a full night’s sleep but I feel guilty about wanting to leave him at my mom’s for that selfish reason. I don’t know what to do...I really need sleep but I also don’t want to feel like a bad mom...