6th Great Grandfathers

Today, in researching my maternal lines, I discovered a familiar name, Groce.  I couldn't recall exactly where it was in my family tree, but upon searching for it I found:

Ann Groce is my 5th Great Grandmother on my Dad's side of the family (b 8 Dec 1785)

My 5th Great Grandmother on my Mom's side's name is Christina Groce (b 9 Jun 1794)
Christina has a sister named Anna (b 27 Nov 1785)

At first I thought they must be sisters, but I have Christina's father as Theobald Groce (b ~1755) and Ann's as Simon Groce (b ~1748).

So are they cousins?

I found immigration records for Theobald and Simon Groce, immigrating to America from Germany on the ship Europa, 20 Nov 1741.  So does that make my Simon and Theobald brothers? or cousins?

I found a table of the Groce Family online and it lists the first Simon Groce in America married to Anna Catherine Schneidelin had three daughters and two sons, Simon (b 24 Jun 1748) and Theobald (b ~1755).  The same dates as my two 6th grandfathers.

This indicates to me that my 6th Great Grandfathers were brothers, and my 7th Great Grandparents on these two lines are the same people!

What a small world!  I'll list out the relations

Simon Groce - Simon Groce - Ann Groce - Ransom Hoots - Ruth Ann Hoots - Delia Arbella Davidson - Clarence Tuggle - Clarence Tuggle - Richard Tuggle - Christina (ME!)

Simon Groce - Theobald Groce - Christina Groce - Wiley Stockton - George Stockton - Estella Stockton - Mary Fern Conner - William Miller - Judith Miller - Christina (ME!)

I think this is accurate, but I'll have to do additional verification.