Augusta ignored
Augusta ignored those who told her she was too old to start bringing up another child. Who else was there? Neville was Frank's, so now he was hers. Her responsibility alone.
Caring for Neville was one small thing she could do for a son who no longer knew who she was.
And she ignored those who said that visiting Frank and Alice at St. Mungo's was a waste of time, and that she certainly should not take the child there. She was proud of her son and daughter-in-law. Her grandson would know his parents, and be proud of them too.