We had a table for 14 once. It was that very large table that is in the middle of the dining rooms. We were a large group and it was great to sit at one big table. We did have to change seats every night so we could talk to other people since we did not want to yell!!! That is the only drawback to a really big table....not conducive to quiet converstation.
Disney has many tables for 10, since you have 2 children, I am sure they could probably just pull up a chair for the 11th person.
MJ