It really does depend on the child and you know your child best.
We went with my brother's family which included my 16 month old godson. He was (and still is) a very active guy. I was shocked that he enjoyed the CP so much (and so were his parents. They couldn't believe it!). Anthony clapped in all the right places and sat quietly on his dad's lap with a smile on his face the entire time. We did eat before the show, which probably helped some.
Anyway, if you are worried about your little one, consider sitting at one of the tables outside of the Liberty Inn. (fast food place in American Pavillion). You won't be able to see much, but you will be able to hear quite well and if your toddler isn't up to sitting that long (about 45 minutes), you won't have to worry about disturbing others.
Best wishes -