Stray cat had gave birth in my basement

This is absolutely insane but for the second time in my life a stray cat has given birth inside my house. Almost 14 years ago a stray cat made its way into my houses stairwell and gave birth (I woke up to kittens outside my door). We kept her and one of the kittens up until a few months ago when both passed away within a few weeks of each other.

Well I can’t believe it but I have discovered that it has happened again. A local stray that has wondered around our neighborhood for years somehow made its way into my basement and gave birth (or carried her newborns inside). I have only seen 2 of them but they appear to be about a month or two old and are fast and good hiders. The mom is aggressive and won’t let us get near. The kittens run away and hide when we try to approach as well. Any tips on how to gather them and get the mom to allow us to? Can they be separated from their mother at this age? Not really sure what to do at this point. We have left the door open and mom comes and goes as she pleases, and I believe the rest of the kittens are outside the house somewhere, but she is leaving these two down there.

Sorry for the poor structure and messiness of the question but any help is appreciated. I’d be open to keeping one and we have a home for another if we can just figure out how to deal with mom and get the kittens trust.