Welcome BACK, Nicole!
A lot has happened since your last visit to The Most Magical Place on Earth. But how exciting that you'll be returning to Walt Disney World Resort with your very own troupe of
Mouseketeers!
In my experience, you are more than welcome to hold a lap child (you can even babywear!) on any attraction that
does not have a height requirement. Specifically with Dumbo the Flying Elephant, you should be fine with a lap child and one sitting next to you.
While it seems like every car and boat (and flying elephant and honey pot) holds a different configuration of people, the good news is that you can find out how you'll need to arrange your crew before you ever get to the boarding zone. There are signs at the entrance to each attraction that notate how many occupants can sit in each row; there will always be at least one Cast Member per queue entrance who would love to help you figure out your seat placement needs; but my favorite way is while on the Disney World website, to
select an attraction name and then click the "View Gallery" button. There are usually photos of guests on the ride, which I use to size up what I'm getting myself into.
Some attractions even have a vehicle out front that are mainly for photo ops, but can be used to figure out your rider placement, to test your comfort, or even ability to transfer into that seat (like from a wheelchair). As a 'Pooh Size' person myself, I can say that you won't have too much trouble on the 'Any Height' attractions with your kiddos. (Now, if you're taller than six feet, like my husband, you might be a bit squished legroom wise. But that's a different Moms Panel question.)
We'll See You Real Soon, Nicole!
~Kristen