We know Anna Christina as the daughter of David and Verena Mertz from her 30 Sep 1728 baptism.  

On 10 Dec 1752, Christina Klein and Jacob Mertz sponsored the baptism of Johannes Litweiler son of Heinrich and Sara. This helps date Christina's first marriage to before 1752. Sara is said in the Longswamp records to be nee Schneider. She was probably closely related to Veronica which would explain the obvious connection of the two families.

Peter Klein and Christina his wife also appear at several baptisms for the children of her nieces and nephews adding further proof that she was indeed Christina nee Mertz.

For a long time, all I knew about Christina's married life was that her husband’s name, from a transcription of tombstones at Longswamp Reformed, was Peter Klein and that she had a son David Klein. In the very earliest Longswamp records in which she appeared as a sponsor on several occasions, she was Christina Mertz but then by about 1752 she was Christina Klein and later she and husband Peter were both named.

What I didn't realize, brought to my attention by Patty Mertz, is that Christina married first Hans Theobold Klein (Kline?) and they were the parents of Margaretha, David, Nicholas and Elizabeth. But then in 1758, Christina married second Peter Klein and they were the parents of Peter Jr. and Jacob.

This information caused me to go back to the records of Longswamp where I found the baptism on 21 May 1769 of Anna Margaretha Klein daughter of Theobalt and wife.

And I also found a citation on Ancestry.com of the pastoral records of Rev. Helffrich which says that Anna Margaretha (Klein) Reber (w/o George Reber) died 22 Jan 1837. She was born Apr 1751 daughter of Theobald and Christina Klein.

So, it certainly does seem proven that Christina Mertz married first Theobalt Klein and married second Peter Klein. Her marriage to Peter was apparently in 1758 and yet there is this baptism in 1769 mentioning Theobalt and Christina. I think the explanation is that there were 8 baptisms recorded at Longswamp on 21 May 1769; it appears to be some kind of catch-up baptismal day. 18-year old Margaretha was baptized, her father indeed was Theobold even though by 1769 he was no longer in the picture (I assume deceased).

Christina is alone among the Mertz immigrants to be buried at Longswamp Church where there is a modern tombstone which says ”Peter Klein 1731-1813 immigrant Christina Klein nee Martz 1727-1789". There is a clear discrepancy between her year of birth as given on her tombstone and as implied from the ship’s passenger lists and her actual baptism. I cannot explain this discrepancy.

Two of her children deserve some further mention. Christina’s son Nicholas married his first cousin Maria Elizabeth Mertz, daughter of Christina’s brother Nicholas.

But her son David is of greater interest to me. I spent a good deal of time in about 2004 working with Patty Mertz (wife of a man named Edgar Mertz) on Edgar's exact lineage. Patty finally determined that Edgar is a Mertz descendant of John Henry through his son John Philip -- the other Berks County line often confused with the John David line. We have now proven through DNA analysis that Edgar and I are not related as Mertzes -- well that is to say we have proven that his ancestor John Henry was totally unrelated to my ancestor John David.

However, Edgar is in fact a (distant) cousin of mine and he is, in fact, a descendant of John David Mertz through John David's daughter Christina who married Theobold Klein. Edgar's grandmother was a Klein, a descendant of Theobold and Christina Klein. Quite fascinating really -- we both descend from John David Mertz, we are both named Mertz -- but our DNA shows no relationship.

Here is Edgar’s line: David Klein and wife Catherine had a son Jonathan born about 1800. Jonathan Klein and wife Mary had a daughter Sara Ann born about 1836. Sara Anna Klein married Reuben C Mertz (great-grandson of John Philip Mertz, the man often confused with my ancestor Philip Mertz) and they had a son Edgar Garfield Mertz born 1881. Edgar Garfield Mertz had a son Edgar Theodore Mertz.

Edgar Theodore Mertz and his wife Patty (Schearer) Mertz grew up in Berks County.

Christina is alone among the Mertz immigrants to be buried at Longswamp Church where there is a modern tombstone which says ”Peter Klein 1731-1813 immigrant Christina Klein nee Martz 1727-1789". There is a clear discrepancy between her year of birth as given on her tombstone and as implied from the ship’s passenger lists and her actual baptism. I cannot explain this discrepancy.

There is a find-a-grave memorial for her, just don’t believe everything written there about her.

http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GRid=42429452