Definitely make your way to Karl Strauss. I moved back east a couple years ago and that is the one brewery I miss above all others. Consider that you can probably get Stone and Alesmith at your local craft beer joint, but you probably won't be able to get Karl Strauss. Also, if you decide to make a day of it in Carlsbad, you can easily hit up Pizza Port for some delicious Lost Abbey/Port brews(and an impressive guest beer list as well).
If you are looking for ale houses where you can taste all of them in one place, I would recommend Neighborhood in downtown or the Encinitas Ale House if you find yourself in North County.
Edit: Just noticed you mentioned kid friendly. Karl Strauss and Pizza Port are restaurants and would be considered totally okay for kids. Neighborhood and EAH during the afternoon would be the same but can get filled up with intoxicated adults later in the evening.