And just so you know, the child doesn't have to do anything but be there. Once he's 16, and gets an adult passport (just so you know, that's what will happen in 2 years), it might be different, I'm not sure. But for now he is a child, and DS just stood there while DH and I said an oath (with right hands raised! right there in the post office! it was kinda neat.) that we had filled out the forms truthfully etc etc.
And because it's worth saying again...if you get the applications and payment in *tomorrow*, it will be less expensive than if you wait until Tuesday, because prices are going up.
Forms are generally at the passport offices (we just use the post offices that are on the state dept's passport site), but you can also download them from their site, find out what sort of payment your passport application office takes (our PO just wanted any sort of payment for their administrative fee for DS's, but then there was a check for the pport fee, for instances), get the birth certificates, make sure the adults have their own identification...get on down to the passport place!