I also have rosacea and it is no fun.
Have your mom go to a department store cosmetic counters and ask for "green base" powder. There is one by Shischado, or something like that at department store.
A powder I am currently using is by Lancome, Dual Finish Matte Buff II. A compact of this powder is about $36 at Foley's or Dillards department stores. This powder helps hide the redness of prominent veins in my face.
I use Benedryl Gel on my face at times. It will be drying and may help clear up acne like bumps. I have a mealy raised rash on my forehead and the Benedryl Gel helps forehead to be more smooth.
Sometimes the rosacea will be worse if the face becomes too dry. I use Neutrogenia Face lotion and sometimes plain Ponds Cream in light blue lid jar from Wal-Mart or other stores.
Best to wear clothes that are cool because warmth will cause face to be more red. Too warm rooms will cause redness too.
Do not drink stimulants such as coffee, tea, alcohol drinks, spicy foods, etc.
Using cold compresses on face off and on will help reduce swelling.