Hi Maria and welcome back to planDisney!
How exciting that you'll be bringing the whole family with you on your next Walt Disney World vacation! I have been visiting the parks since I was little, both at Walt Disney World and Disneyland, so it's extremely heartwarming to be able to make new memories together with my parents and my own kids. Multigenerational trips are the best!
When making your
Disney dining reservations, every Guest needs to be included in your party size, no matter their age. This is to adhere to the maximum occupancy set by the fire department. Even if your littlest grandbaby won't be eating or sitting in a chair, they will still count for occupancy.
Dining reservations open up 60 days in advance, so have an idea of where you and your group would like to dine during your trip. It might be difficult to get reservations for 13 at once, so you may have to look into breaking up into smaller groups to be able to accommodate all of you. When I'm making group reservations and need to have more than one at a time, I arrive at the restaurant a little early to ask if it's possible that we can sit together or near each other. It's not guaranteed, but the Cast Members have always done their best to accommodate us.
If you will be visiting
Disney's Hollywood Studios during your next vacation, I highly recommend the brand new
Roundup Rodeo BBQ in
Toy Story Land. We had lunch there a couple of weeks ago and it was not only delicious, but so much fun! My kids loved the "surprise" visits from Andy and it's always nice when a restaurant does things that are a bit unique. Roundup Rodeo BBQ has the capability to seat large parties, so this is definitely a place I would consider for your family.
Please stop back by and visit if you have any additional vacation planning questions.
Have a magical day!
Leslie