Most JW's do not believe what your mother does not. Here is an interesting thought to share with her.
If Jehovah is "being patient" and allowing more to come in that is fine, but he is also making sure that more people born will die.
Just look at it this way. These are rough numbers but pretty close. the point is clear.
Every year around 130 Million people are born. About 50-55 Million people die that same year (includes all deaths).
Last year 265K were baptized (and by guess, roughly 60-80K were disfellowshipped).
So every year Jehovah is patient, he is going to have to kill another 75million or so people!
Does that make sense? I think she is reading that scripture with meaning that has been supplied to her, but not the meaning intended. Or the bible could be kooky.