There have been certain times over the years that families have requested a family group portrait with a theme. Often these portraits reflect and show their devotion to a favorite sport team as you can see in this portrait with the family wearing the Minnesota Twins jerseys.
Some of other theme portraits I have taken showcased golf,and flying (family member was a pilot.) These portraits are a lot of fun to create and generally give a more of a relaxed, casual look to the portraits.
I do recommend to the families that it is always a good idea to also take more traditional portraits with their regular clothing, too. That way, they can pick and choose between the 2 options when they view and order their portraits.