We always have a joint birthday party for Max and Drew, and they love it. We keep it simple. No big party with a theme and favors and activities. Just the people we love, some good food, and two cakes.
This is the first year it has been warm enough (North Carolina spring means it can be 50º one day and 75º the next...and their party is usually on the cold day) for us to actually have it outside, and we were so excited about that. People piled onto the picnic tables to eat, and the kids could all play and have fun.
Our house is also in the middle of a significant paint color change, so just ignore the crazy looking trim in these photos. Oops.