Wouldn’t that be like marrying your own MIL?
According to Mormon historian Todd Compton, in his book In Sacred Loneliness: The Plural Wives of Joseph Smith, Smith entered into the following polygamous marraiges:
In summary, out of Smith's 33 plural wives, twenty were under age 30 and thirteen were over age 30. A third of all the wives were married to someone else when Smith took them.
Depends...
Who did he 'marry' first?