I was watching the BBC news at ten last night and when this story came on they showed film of Sian Phillips as they told of the sad death of Margaret Tyzak.
I expect the confusion came from the fact that they were both in I Claudius, but I thought the BBC was very thoughtless in not checking they had the correct clip to show.
Margaret Tyzack was in the Forsythe Saga and also played Claudius'mother in I Caludius in the 1980's.
The One Show showed Sian Phillips when they announced it. She is alive and kicking and appearing in a play in the West End!
She left EastEnders after a week or so and this must be why - she was ill.