My sister-in-law owned a tablet and passed away two years ago my broth

This is old enough it doesn’t have Google FRP, but it’s a Jelly Bean tablet - barely anyone supports it these days. You'll need to get most of your apps through app repositories who archive final versions, but if you’re okay with that then you can reflash the tablet with the factory ROM - providing you can find it. This just comes off as a drugstore tablet with how low spec it is that you would only ever find at CVS or Walgreens.

The issue here is this is one of those “blacklisted” tablets by anyone who knows better, so finding it won’t be easy and cracking it isn’t practical. See if this has a recovery mode where you can reset the device from the recovery menu as that’s your best bet. It’s usually Power+Volume down, but it can also be volume up on some of these. Try both and see what works. Only do this if you don’t need the data.

Sadly this has met the end of it’s life :-(. Not enough storage for a supported version, 1GB of RAM and the SOCs won't support anything remotely modern in almost all of these. Move on if you can’t use recovery mode or find the ROM.