Question

With God’s help,
Hello Rabbi,
I wanted to ask a question that is a bit complicated, given that I’m missing a lot of knowledge about the details of this case, and precisely because of that I think it’s appropriate to ask.
We have at home a kind of cleaning lady about once a week, who also cooks sometimes. She was originally a non-Jew, but she converted, and as a result the whole family went to a religious public school. The father is originally Jewish, and he did in fact become religious following the conversion, and some of his children are indeed religious. About the younger children, I don’t know enough.
The issue is that, from what it sounds like, she has pretty much stopped being religious by now. I don’t know whether she publicly desecrates the Sabbath, but let’s say she didn’t fast on the holy days we recently had. In contrast to the first years (say 4 years, if not more), when she observed more commandments, it still never seemed like the very most observant, but at the very least more like traditional-plus or weakly religious.
If so, is there reason to be concerned about food cooked by a non-Jew?
Of course, the implications of that are pretty serious… and also for the rest of the children she may still have. And I’m also not sure whether it would be advisable to look into more details…
Theoretically, maybe one could rely here on the leniency of the Rema in pressing circumstances, since at home we always stoke the fire.