Celebrities and entrepreneurs who have made fortunes like Daniel Craig, Warren Buffett and Kevin O'Leary are worried about leaving too much money to their children.

According to a survey by The Motley Fool, cited by CNBC, which involved 2,000 people with net income over $1 million, 67% of respondents revealed concern about leaving too much money to their children.

The main concerns are that the money will be used "irresponsibly" or that the children will become "lazy" because they have a large inheritance.

"They are aware and even consider leaving inheritances under conditions, which encourage their heirs to acquire values they consider important, such as hard work, doing well in school and having a good career plan," Jack Caporal explains to CNBC, one of the analysts.

The study found that 85% of the multimillionaires had to meet certain conditions in order to receive their own inheritance.

Only 78.5% of those who received inheritances between $100,000 and $500,000 agreed with the conditions, while only 69% of those who received less than $100,000 approve of this strategy.

But despite their concerns, 60% of the respondents said it was "very important" to leave an inheritance and some 34% stated that they planned to leave more than 50% of their estate to their children.