She SAID she asked and they told her she's been checked a couple of years ago for B12???So they didn't need another test
paddyann I don't know if you would be able to phone her surgery, speak to the practice manager or a doctor, express your concerns, and ask them to send an appointment for a 'check-up' and let you know as you would 'need to take her'. They won't discuss her with you, of course, but you could say that you wonder if she needs a blood test and a review - do they run a 'Well Person Clinic?'.
I know how difficult it is, my MIL would never do anyone we suggested and would just say "You don't seem to understand, dear, I've always done that/never done that" etc.
We decided that we could never persuade her and ultimately, she was perfectly capable of making her own mind up.