Fast pass with a rider swap

[hbentleylll]

We will be traveling with 2 adults and 3 children. Two of those children will be tall enough for things like test track, tot... but then we will have a 3 year old who most likely won't (we raise short kids )

When we have fast passes for these how does rider swap work?
Would they allow us the get a rider swap and then each parent would ride with BOTH kids?
Or would they expect us to each ride with one child only and not use rider swap?

 

[ArielSRL]

Only 1 parent needs a FP. Have the older kids get one as well. Parent 2 and younger kid can get a FP for a non restricted ride (or parent 2 can get a FP for another thrill ride).

Everyone goes to FP entrance, show too short child, get rider swap. Parent 1 and two older kids ride. Then, sometime in the future (pass is usually good until end of the month), parent 2 rides with two older kids as the pass is good for up to 3 people.