We usually have 4 in a 2-bedroom -- not 9 -- but we've had a total of 8 when we've had overnight guests (duly registered with the front desk). And we managed just fine.
The good news is that the 2-bedroom units at OKW are very spacious -- over 1300 square feet if I remember correctly. WIth 2 bedrooms, 2 bathrooms, a big living-dining-kitchen room, and a large balcony, there is plenty of space so that the 9 of you can be together or spread apart.
Do the 5- the 6-year olds have the same parents? If so, put that family of 4 in the the second bedroom (which has 2 queen size beds and a private bathroom).
Grandma and Grandpa get the master suite, and the king size bed. The third couple has to sleep on the pull-out sofa in the living room.
The 1-year old in the portacrib can go in any of the three rooms, but would probably end up with the baby's parents.
Well, it's not ideal. But it would seem to work.
A Grand Villa would be perfect, but they're hard to get and require a lot of points.
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Werner Weiss, Curator of
Yesterland, featuring discontinued
Disneyland attractions