I am off in a bit to take my elderly mother shopping for her outfit to wear to my son's wedding...HELP! I guess I should have been scoping things out before we go but I didn't:(

Mom is disabled and can walk just a few steps with a walker, needs sturdy shoes and has an expanded waist that will make dresses next to impossible. I'm thinking more of a nice pants outfit with an elastic waist and a nice topper. The wedding is in August so temperatures will be warm. I'm thinking of Chico's and perhaps Coldwater Creek. Am I headed in the right direction? Any other ideas would be greatly appreciated!

Thanks!