Dakota Johnson's grandmother has been an example of ''what never to let happen in life''.

The 28-year-old star's grandparent, Tippi Hedren, has been hailed a great mentor for her granddaughter as she refused to work with Alfred Hitchcock on a movie after she claimed he harassed her.

And the 'Fifty Shades of Grey' star's mother, Melanie Griffith, believes she has also contributed to instilling a ''strong'' work ethic in her child.

Speaking to The Hollywood Reporter, Melanie said: ''She became an example of what to never let happen in my life. Hopefully, I've passed that on to Dakota - to be strong in your work and in yourself.''

However, Dakota has admitted her family have not explicitly warned her off of ''powerful men in Hollywood'', although she was taught ''self-respect and grace and strength''.

She said: ''I was taught self-respect and grace and strength. Never before this moment did anyone in my family [explicitly] say, like, 'Be careful.' Sometimes, powerful men in Hollywood will try to whatever.''

And Dakota - who is believed to be dating Coldplay's frontman Chris Martin - has been hailed as the most successful star in the family.

Melanie quipped: ''Dakota's the only one who's getting scripts.''

However, Dakota's father Don Johnson, 68, has revealed the industry is fast-changing, as he has noticed there are times when people are a ''pretty big deal'' and moments when stars are ''not such a big deal''.

He said: ''There are things we have to manage [as actors]. You have times when you're a pretty big deal, and then when you're not such a big deal. What it all comes back to is the work and how much joy that you get out of doing it.''