Generally, the provisions of the plan document determine the distribution options available to beneficiaries of retirement plan assets. From a regulatory perspective, you are allowed to distribute the assets over the life expectancy of the oldest sibling. If the assets are allocated into separate accounts by December 31 of the year following the year your parent died, then each sibling is allowed to use his or her own life expectancy to calculate required minimum distribution amounts.
If your parent was retired but passed away before the required beginning date, then you have the option of receiving your payments over five years or less. But this will only apply if the beneficiary did not begin distributions using the life-expectancy method by December 31 of the year following the year your parent died.
To be sure of the options available to you and your siblings, check with the administrator for the defined-benefit plan.
For more information about inherited pension benefits, read Inherited Retirement Plan Assets - Part 1 and Part 2.
This question was answered by Denise Appleby