You can withdraw your original contributions to a Roth at any time. But you must wait five years to avoid paying the tax on earnings on regular contributions and you must be 59 1/2 years old.
If you inherit a Roth from your spouse, the taxable period ends either five years after the account was opened by your spouse or five years after the surviving spouse opened his own Roth, whichever is earlier.
A surviving suppose can name his children as equal beneficiaries of the same Roth. It is in the children’s interest to do so. Any heir other than a spouse who treats the Roth account as his own must take the required distributions from the Roth beginning by December 31st of the year after the year of the previous owner’s death. If the children keep the account intact and they want to stretch the withdrawals as long as possible, they are restricted to using the oldest child’s age. However, if they split the account, each sibling can stretch the distributions across his own lifetime. This means younger siblings can spread withdrawals over more years, leaving more assets in the account for a longer time and most likely realizing more tax-free earnings.