Please give the personal information of the married employee who has the highest pay rate.
married refers to MaritalStatus = 'M'; Highest pay rate refers to Max(Rate)
SELECT T2.Demographics FROM Employee AS T1 INNER JOIN Person AS T2 ON T1.BusinessEntityID = T2.BusinessEntityID INNER JOIN EmployeePayHistory AS T3 ON T2.BusinessEntityID = T3.BusinessEntityID WHERE T1.MaritalStatus = 'M' ORDER BY T3.Rate DESC LIMIT 1