Don't be sorry. Cats poop! It's all part of owning (being owned?) by cats.
Cats, unlike dogs are obligate carnivores, meaning they can only digest meat (no grains, no veggies, no fruits). Unfortunately, even though chicken is the first ingredient in the food you are using, the next 5 ingredients after that are all not actually really digestible for your cats and actually make up the majority of the food. Say 10% is chicken, then 9% is wheat, 8.5% is rice, then 8% is corn, you have almost 30% of the food that is not digestible. This will strongly contribute to both the color and consistency of their stools.
I do want to note that she could have inflammatory bowel disease, or colitis (since there is no weight loss) as well, and if that is the case, changing the diet to something that is more digestible will help and possibly fix it completely.
If you have the time, I strongly recommend you read more about cat nutrition at catinfo.org. I know her articles are very long, but she is a vet who has put many years into them. It completely changed how I look at cat food, especially the moisture part.