That doesn't sound right to me - if someone is saying this is pursuant to Washington law I'd like to know what provision of the RCW they think says that.
A person that inherits an IRA should be able to designate their own beneficiary. That said, the IRA distributions cannot be stretched to outlast the life expectancy of the first person to inherit it. For example, if the person that first inherits an IRA has life expectancy of 40 years at the time he or she inherits, the IRA account must be distributed in that 40 year time frame. If the person that first inherits lives 41 more years there will be nothing left of the IRA to inherit by the next generation. However, if the person that first inherits only lives 30 more years, there will be a balance in the account to be inherited by yet another generation. However, the person that second inherits the account cannot stretch distributions over his or her own life expectancy. The best that the person who second inherits the account can do is finish the 10 years of distributions (the remaining life expectancy of the now deceased first inheritor).
Don't get stuck on the numbers I've described - they are only sample numbers. It's the concepts that are relevant.
The foregoing is commentary regarding a general legal question. It is not intended to be legal advice specific to the reader's individual situation nor does it create an attorney-client relationship between the author and any reader. You are encouraged to contact a qualified attorney to discuss your legal situation.