From WENN.com

The veteran actor/director, who turns 89 next month (Aug12), is wheelchair-bound after a 2008 fall, and his brother, Sir David Attenborough, revealed last year (11) that the star ""won't be making any more films"" as a result.

The Oscar-winner's son Michael subsequently told how his father ""finds it hard"" to communicate, and he has now revealed his mother, Sheila Sim, is facing her own health crisis.

Michael Attenborough tells Britain's The Stage newspaper that Sim is suffering from senile dementia, and in a separate interview with the Daily Telegraph, he adds, ""I'm running their affairs for them now, so there is a lot when I see them that I have to tell and bring them up to speed about.""