Okla. Stat. tit. 46, § 46-5: Mortgage follows property passing by succession or will

When real property, subject to a mortgage, passes by succession

or will, the successor or devisee must satisfy the mortgage out of

his own property, without resorting to the executor or administrator

of the mortgagor, unless there is an express direction in the will

of the mortgagor that the mortgage shall be otherwise paid.