(Cover) - EN Showbiz - Liv Tyler is helping her grandmother Dorothea Johnson write a book about etiquette.

The actress is teaming up with the matriarch of her mother's side of the family to write a book about manners.

As well as being Livs grandmother, Dorothea is the founder of the Protocol School of Washington

Titled Modern Manners, the guide is described as a "lively and approachable" read that will highlight the importance of good manners in today's digital world.

This is the 33-year-olds first foray into literature.

The daughter of Aerosmith rocker Steven Tyler, Liv is best known for her acting roles such as her portrayal of Princess Arwen in The Lord Of The Rings series.

She has also starred in various modelling campaigns for fashion house Givenchy and denim brand G-Star.

Publishing house Rodale Books have acquired the world rights for Modern Manners, which is set to be released in May 2012. (C) Cover Media