Do wonder what makes you say you have just 'two years left'. My ex-husband kept repeating that he would die early due to side effects of MS. On his 65th birthday, I did point out that even if he died that day, whereas sad, it could hardly really be listed as an very early death. That was 14 years ago, and he is still going strong!!!
If there is only a small state pension due to the 16 years this person was in employment, then they can claim Pension Credit to bring the amount up to the standard State Pension amount.
I am one of those horrified that she states that her adult children will 'look after' her. Surely, she does not want nor expect this. As they were obviously only born in the 90's they are quite young, and are likely to have, or will shortly have, their own young families to care for.
All she has to tell HMRC is that she was a full-time Homemaker in the years they are asking about,.