While this in of itself was not too worrying, a scene featured later on in the show’s premiere certainly worried fans.
During the discussion about Alan’s brother Ted (Timothy West) returning to England from New Zealand, Celia was telling of Ted’s supposed progressing dementia.
After this discussion Alan looked into the middle distance while adding: “I didn’t know he’d started with dementia.”
To which Celia replied: “Well he’d have been hiding it, won’t he? Like folk do.”
source: express.co.uk