you can speak to your dad's doc and ask him to test your dads blood level. if he is taking all of his pills like he is supposed to, his levels will be up to par. If not, you will know he is missing doses. Since you havent seen momma take those pills, and you dont know for sure its happening, a good place to start is with dad. Getting his levels checked will give good evidence. Ask the MD to not give any warning that he is going to check those levels. If he comes up shy, that is an open door to start a dialogue with mom about her condition. Without evidence, it will add to her burden if she thinks others are keeping tabs on her.

tough spot to be in. hang in there.