MIL.
Over time have got her dressing gown, slippers, gloves, scarves, nice toiletries an Alexa. She's likes / uses them all (though not quite sure she knows who they came from but that's not the point). They don't need replacing.
Books, jigsaws etc. are not a great plan for obvious reasons... she forgets she's read them or gets frustrated. If we buy her food she binge eats because she forgot she's eaten already.
She's got all the home furnishings etc. she needs, piles and piles of stationery.
I'm at a complete blank (weirdly if don't get her anything she will remember. If she does not like it she will keep talking about the fact I got her something she does not like and if she DOES like it she will keep saying "look what DSIL got me". Normally she likes it but I honestly do not know this time.