looking for info on John Henry Ehlenberg, from Venne, Germany

Both of my parents lived somewhat east of Pittsburgh. My mother's g-grandfather was John Henry Uhlenberg, who was born in 1822 in Hanover, and sailed from Bremen, arriving in Baltimore on 25 May 1840. He indicated his place of origin was Venne, Germany, but he was the only person of that name on that voyage, so I'm not sure that I would find any information about him in Udo Thoerner's Venne book.  Mr. Euhlenberg had at least one daughter, Mary Eva, who was born in Wexford PA in 1847.  One of Mary Eva's daughters was Alice Elizabeth Grubbs (1869-1957), and one of Alice Elizabeth's daughters was my mother Mary Grubbs Welshon.

If someone knows anything else about John Henry Uhlenberg or Mary Eva Euhlenberg, I would enjoy hearing from you.  I am James Muir, in Austin, TX (jm20@txstate.edu).