Warren Buffett reveals brutal rule all parents must follow to keep their family together

America's most famous investor has given advice for all parents - regardless of wealth - to let kids read their will. 

Warren Buffett said parents of either 'modest or staggering wealth' should let their children read their will before they sign it. 

The father of three, who has amassed a $150 billion personal fortune, advised parents in a letter on Monday that each child should 'understand the logic for your decisions and the responsibilities they will encounter upon your death'. 

'If you have any questions or suggestions, listen carefully and adopt those found sensible,' Buffet said. 'You don't want your children asking 'Why?' in respect to testamentary decisions when you are no longer able to respond.' 

A certified financial planner, Douglas Boneparth, told CNBC that he agreed with Buffett's advice. 

'These are tough conversations to have, but they're meaningful and when approached correctly, can strengthen relationships,' he said. 

'You want your children to have realistic expectations about their inheritance.' 

Boneparth, founder and president of Bone Fide Wealth in New York City, added: 'Kids' imagination can run wild with what they think they should be getting.' 

He added that parents should be as clear and thorough as possible about who will receive what and why, so that any tensions or hurt feelings can be addressed while you're there to answer. 

94-year-old Buffett recalled in his letter that over the years he has witnessed 'many families driven apart after the posthumous dictates of the will left beneficiaries confused and sometimes angry. 

'Jealousies, along with actual or imagined slights during childhood, became magnified.' 

Boneparth added that it's important to explain why certain inheritance may not be split equally and why. 

For example, one child might be more financially stable and another might need more help. 

Carolyn McClanahan, founder of Life Planning Partners in Florida, said that parents should also be mindful of their child's financial situation and history when deciding to discuss their inheritance. 

She said that in rare cases, it might be advisable for parents to be more cautious with a child who has exploited them financially or if a child is irresponsible with jobs or money.

Learning that they stand to inherit a large sum could deflate their ambitions and any drive to succeed on their own even further. 

Buffett also talked about why he will not be leaving his large fortune to his children, but instead giving away 99 percent of the money he's made through his company Berkshire Hathaway.

Buffett wrote: 'I've never wished to create a dynasty or pursue any plan that extended beyond the children.

'I know the three well and trust them completely. Future generations are another matter. Who can foresee the priorities, intelligence and fidelity of successive generations to deal with the distribution of extraordinary  wealth amid what may be a far different philanthropic landscape?' 

He named three independent trustees to oversee his philanthropy following his three children, anticipating that his wealth may take longer to disburse than his children live.

Alongside the appointment of trustees, Buffett also donated an additional $1.1 billion in Berkshire Hathaway stock to his family's four charitable foundations. 

The identity of the trustees is not known, but he said each is well known to his children.

'They are also somewhat younger than my children,' Buffett wrote.

'But these successors are on the wait list. I hope Susie, Howie and Peter themselves disburse all of my assets.'

Buffett has been making yearly donation to the four family foundations since 2006.

These are The Susan Thompson Buffett Foundation - which is named after his late wife - The Sherwood Foundation, The Howard G. Buffett Foundation and NoVo Foundation.