I notice the way he keeps saying 'the estate', as though it were some kind of neutral goodwill organisation - when what he really means is himself and the other siblings, who weren't bothered about looking after their Mum, but are bothered about getting their hands on her money... money that would already have been more than swallowed up by a care home, had Bern and her DH not stepped up and accepted a big restriction on their own lives and freedoms in order to make her DM's remaining years as pleasant for her as they could, according to her own expressed wishes.
Also, £50 a week 'keep' is what you ask from your young adult kids when they've just started earning, as a token contribution and to help them on their way to learning about independence in the adult world. Housing and caring 24/7 for an elderly person who is suffering with dementia could not be more different from that.
Complete bunch of CFs - at least their DM was lucky enough to have 1 DC out of 6 who did care about (and for) her.