Johanna Wittrock

Any information concerning the following would be most helpful and appreciated.

Johanna Wittrock
Emigrated to Philadelphia with husband Herman Wittrock sometime 1895-1899.
They took ship from Oldenburg area (via Hamburg?) May have lived in Oldenburg for a time.
She was resident of Cloppenburg in 1897 at age 26. She was resident of Philadelphia 1904 at age 32.
I believe She had daughters named Marie and Anna and a son Hermann.
My mother’s name was Anna Wittrock born 1900 in Philadelphia. I believe Johanna may have been my grandmother.

Any help will be most appreciated. I do know my grandmother emigrated from Oldenburg (Hamburg). And I do know she was back in Oldenburg for a trip with daughter Marie in 1904 based upon shipping records of passangers.

Thank you for any help.
John F. Stead 434 Fitzwatertown Road, Willow Grove, PA.
Can be emailed at jfstead8@comcast.net or steady88us@yahoo.com