At the moment mum is allowing me to pick and help her dress, but there was a time when I could not get her to put anything on that I thought appropriate, only happy to put on her coat in the house and so I let her, at least I knew she was warm. This summer I bought at lot of thermal underwear and whatever she wears on top of these is a bonus. Have you thought about buying a halogen heater - don't understand the science, but I think they are supposed to warm the core of the body rather than the whole room, when keeping her warm in the house I used one. These days her hands tend to get cold so I let her wear gloves and of course we have an open fire and she loves standing in front of this, rubbing her hands together and warming them up.