Any normal garb would be good- lots of variety (cool weather and warm weather T-tunics and pants). I would personally just bring your own play yard unless your camp has serious objections- you know it works and you know its SAFE. If you want a more period look throw some canvas over it and call it a mini-ger/yurt. I'm taking my 5yo after a long break- she's been potty trained for a few years now and I think I'm still going to bring a kid's potty or a camping potty for nights. Also, porta johns can be scary, even to me!

Hope this helps. I may have more advice after this Pennsic with the 5yo!

I have a 4 year old boy. I have taken him to events since he was 6 weeks old.
My number one advice is to camp with other moms. I did Gulf Wars without other moms in the group and it was not much fun for me at all, as I had no one to leave him with if I needed/wanted to ... say, use the porta john or something! So the logistics of that was a little difficult.

As someone posted in another thread, children are durable and washable. You have two boys. If they are anything like mine, they like dirt, and lots of it. Mine is perfectly happy at Pennsic digging in the dirt. No fancy garb for him - just plain, simple tunics. And lots of kid-friendly soap.
I take a pair of sneakers and a pair of sandals for him. Period shoes are just not something I worry about for him.

A WAGON. We have a great ATW Radio Flyer wagon. It has inflatable wheels that make for a nice ride, and it handles well in the Pennsic terrain. My son LOVES going for rides in the wagon, and it saves my back from carrying him when he gets tired of walking (or has a fit.)

Food. My son eats a LOT at Pennsic. I kid you not, one year we went to Pennsic for 2 weeks and when we got home his mundane clothes were too small. Bring lots of snacks. And beware... I have a camp-mate with a child a year older... and as is the way with kids, each wanted to eat what the OTHER mom had packed. Eventually we just agreed to feed each other's kid, because it seemed to keep them both the happiest. LOL.

Good luck, and don't forget to check the schedule for all the children's activities going on around Pennsic... 4 year olds are big enough to participate in most! :o)

Well my son will be four at Pennsic this year and for your case we can just double the trouble. Drew is active and enrgetic and he learned to pick up the play yard and carry ti where he wanted to go in about ten munites time. We considered something along the lines of a "Baby Run" with a harness and leach on the child attached to a pulley on a clotheline (like a dog run) but realized that would be veiwed baddly. BUT the harness and leash wasn't a bad idea at all. We found a little thing at Wal-mart that is a backpack in the form of a monkey and the monkey's tail is looped on the end to be a lead. I merely replaces teh lead with an extendable reel type dog leash for small dogs that give a ten foot lead. This gave me total control over Drew and he could still get some room to explore. Some people gave me a hard time but then I realized those people weren't parents and it was the parents of small children that were all asking me where they could get one... I also got a wagon with a shade umbrella. I set it up with a cozy blanket and quiet toys. Drew liked to sit int he wagon. He waved to people we passed as if he were soem kind of royalty. To keep him from climbing out on his own at first I put a portable dinner seat with buckle staps in the wagon and would be abel to buckle him in but after a little while I didn't need to do that because he wouldn't want to climb out. When we went to watch battles I gave him a wooden clapper noise maker that we found at a craft show so he could sheer and hollar and make allthe noise he wanted. He could sit in the wagon and get all wound up and cheer for the game like he was at a Football game. This served to get the crazy out of his system and he wsa tried by the time we got back to camp.

The potty thing is a good idea. Make sure the boys will use it ahead o time. My son never took to the potty seat. HE wanted to use th "blue box potty" - so I took a mini toilet seat with me. The kind that sit on the regular toilet seat and just amke it small enough to keep lilttle tushes from falling in.

Pennsic last eyar was also the first time Drew slept in his own bed. I brought him a folding camping cot and made it a little more comfy with some foam and familiar blankets. It was the first time he laid down a a nap on his own. He just decided he wanted to read his Winnie the Pooh Book and curled up and fell asleep.

I bet I will have lots more stuff to tell you when we get back.
Garb for Drew was lots of longish tunics that he would sometimes were alone over a pull up or with pants. We also had a little cheater kilt (a pleated wrap around) made for him. A wide brimmed hat was crutial, drew is partial to an African looking wide cone hat we found in the market at Pennsic.. Sunscreen was very important. Drew most preferred his Medeivol Moccasins (the leather strappy celtic shoes) we buy him a new pair each year at Pennsic. I also bring him a pair of aqua shoes and a pair of sandal and a pair of sneakers.