I'm even worse than your mom - I color my roots every two weeks. Of course Knotty is right - if your mom can color less frequently, it's better for the hair - but since I color more frequently, here's my advice.
This is what I've found helpful to keep my curls lively.
Use Curl Junkie Repair Me as a protein treatment the time before you color, in other words, if you color on a Saturday use the CJ Repair me when you wash your hair the time before that like on the preceding Wed., or Thurs. Right after the protein treatment, in the same shower, use a deep conditioner like Curl Junkie Curl Rehab.
Then when you color your hair, use a mild color protecting sulfate shampoo to get out all the color and more Curl Rehab, or if your mom uses cones, she can use whatever conditioner comes in the box of color.
Every other time I shampoo, I use a non-sulfate poo and lots of non-sulfate conditioner and I avoid cones in my stylers. Once a week I repeat the protein treatment, deep treatment, even if I'm not going to color that week.
Hope this helps!
2/c and some 3A. Modified CG.
Highly porous. Color over grey.
Best 1st day method: Super Soaker
Conditioners: Curl Junkie Beauticurls Strengthening Conditioner,
Deep condish: Curl Junkie Curl Rehab
Stylers: Experimenting with cones & sulfates while the dews are high. Sometimes try roller sets - classic glamor but I prefer my curls.
Every day is a gift