It could mean that he thinks your mothers diabetes is not genetic, but rather caused by another reason. Many older people develope diabets from a number of causes.
when your mom gets her glucose meter, why not do a poke. It will give you an idea fo what she has to do, give you teh ability to do it if anything happens, and it will give you a good clue if you have to worry.
Also if you choose to poke yourself, do it in the morning before eating anything to get a really good idea if you need to worry.
Half the time I cant find my meteres because my family plays with them too, just to keep in check!