Choose what YOU feel great in! Start by choosing Mom's outfit and then plan the rest of the family around her. Avoid matching clothes--i.e., kids matching each other or a parent. Instead, choose clothing that coordinates. It'll look much more natural on camera.
I'm happy to be a sounding board for wardrobe consults-- text me some photos and we can talk it out, or better yet, just bring everything you like with you to your session and we will figure it out together! If all goes well, we can do more than one outfit.