United Kingdom, Dec. 8 -- Ethan Hawke has insisted Robin Williams' mental health struggles were "obvious".

The Training Day actor starred with the late comic - who took his own life in 2014 at the age of 63 - in the 1989 classic movie Dead Poets Society and he insisted the death of Robin doesn't change how he looks at Peter Weir's movie now because he was always aware of his co-star's "complex" feelings.

Speaking on CBS Sunday Morning, Ethan said:

"It does not fundamentally change the way I watch the movie because, even at 18, I was aware of the complexity of his emotional life.

"I've had a lot of depression in my family, and it was obvious to me that all that power and that charisma came at a certain cost. [He was] a deeply, deeply s...