Close to Wild Dunes I would suggest the Boathouse between Isle of Palms and Sullivan's island. It is good fresh seafood. you can eat upstairs and watch the dolphins play in the current. Not cheap but good value for a resort location.

Two other fun places are the Marino on Lockwood Drive (other side of Charleston pennisula.) It is less expensive and very casual. Never know though. You might be eating with multi millionaires who are mooring their yatchs. It is entertaining watching the boats come and go.

My favorite (non seafood) family place is on the other side of Ashley river. California Dreaming is a fun place. You can get a window seat.

Thank you for the suggestions! Seafood is definitely on our must-do list. Charleston is full of so many great restaurants but all of the ones I've read about do not seem child friendly. We don't want to ruin another diner's experience or have our kids be uncomfortable, but we also don't want to fill our vacation to such a foodie city with McDonald's and pizza!

It might be fun to go to The Wreck for seafood. We eat at very nice places at our beach and have always taken our grands at any age. I believe children are welcome anywhere if they are mannerly. And this comes from a grandmother who also has some grands who indeed were difficult to take out--and I stopped doing it until they were reminded of how to act when out in public.
Someone from Charleston will have to describe how to get to the Wreck!! It's very kitschy, and has acceptable seafood.
There are a lot of places on Shem's Creek that would be fine for a family.

Closer to you than the Boathouse is a similar restaurant called the Morgan Creek Grill. It's a little less expensive and just a bit more kid friendly. Both have good seafood and great water views - can't really go wrong with either. Both take reservations on OpenTable.com - definitely do this with such a large group to avoid waiting.

The Wreck is on Mt. Pleasant near the Cooper River bridge. It is a wrecked boat pushed up by hurricane Hugo. It is very informal. You will sit at wood tables covered with butcher paper and be given a mallet to crack crab. Good views.

P.S. I meant to recommend the dinner at the marina not marino. I still can't spell yaht though.

Most of the nice Charleston places are very child friendly, but they may not be child centric. High Cotton has coloring books and a kids' menu. 82 Queen has a nice patio. The only place I don't remember seeing families having supper is McCrady's.

You might want to also consider Poe's, Home Team BBQ and Taco Mamacita over on Sullivans. There are also some good places just across the connector in Mt P: the Mustard Seed, Boulevard Diner, Crave, Page's Okra Grill. All have families all the time.

The Wreck is back on Shem Creek between Magwood's and Wando Shrimp. No signage. I like it a lot but they don't take reservations or credit cards.

You'll want to take Brian's advice and make reservations with a group that large.

Sue, I think someone mentioned recently in response to me that they are taking credit cards now. But either way, good to know.

Beter safe than sorry! Finding one's way out to the ATM and back in again after dark could prove problematic

We love Poe's, Home Team BBQ and Taco Mamacita's and the whole downtown Sullivan's Island scene. It was hard choosing Folly Beach last year for our annual Charleston beach trip knowing we'd miss out on these 3 places. If you really want to go to Poe's though, either go off hours or plan on a serious wait.

Due to your children's ages and preferring moderate priced restaurants, I would also recommend the Shem Creek area in Mt. Pleasant. All are seafood oriented.If your timing is right the shrimp boats will be coming in and docking right in front of you.

IF it's shrimp season. I like the places there, but I always say, they're more about the views than the food. But the views are amazing.

The town has built a nice pier through the marsh out to the creek on the Vickery's side. It's a great walk after lunch.

We had a group of nine on vacation on Sullivan's Island last summer, including a 4 and 6 year old. We had a great time at Fleet Landing. They were very accommodating and the kids were completely content there. We also had a good experience at Five Loaves Cafe. The girls also loved Poe's Tavern, but we split into a smaller party and ate early that night, because as Brian mentioned, it is packed at prime dining hours. That is the one drawback to the majority of the Sullivan's Island restaurants. Our worst group experience was at HomeTeam BBQ, where we had been told a table would be ready in 10 minutes, but instead had to wait nearly 45 minutes. It may have just been us, but no one was really happy with their food, once we finally got it, plus we were seated out on the front patio, which faces west, so the slowly sinking sun was blazing on us, the flies were swarming, and everyone was just generally grumpy.