Hey Howdy Hey Jessica and welcome to planDisney!
While vacations to the Walt Disney World Resort are vacations perfect for the whole family, admittedly, these can be long days in the parks. I am a huge advocate for taking breaks mid-day to get out of the hot Florida sun and recharge for a night of fun in the parks. Logistically this may be tough if part or all of your party are staying offsite, but let's talk about taking that mid-day break!
In my experience, having Guests over at your Disney Resort hotel during the day, even if you are not there, is totally fine. The issue would be if they were staying the night with you all. As long as it is just a couple of hours for a mid-day break, you shouldn't have any issues. Your only potential problem would be having a way for them to get into your room!
If you have
MagicBands or a MagicMobile Pass, you can give your in-laws one of your MagicBands that will unlock the room while touring the parks with your MagicMobile pass. You can also stop by the front desk to get a Magic Key card that will open your resort room as well and give them one to use.
I hope you and your family have an Enchanting vacation during your upcoming stay. If you have any other questions, feel free to let us know, we are always happy to help!
To Infinity and Beyond,
Nick