Valerie
The tale is rather a rambling one so I will try and cut it down a bit!
Thomas Rowlands 1784 - 1850 m Mary d 1851 - Wisconsin both of them interred on their farm we understand.
However, TWIST one, patronymics plays a part in all this. Thomas' s two children left in Wales we have traced under surname Thomas - the son taking the fathers first name as a surname. They did not revert back to "Rowlands" until their fathers generation in the locale died.
TWIST two -Thomas was one of five brothers the other 4 remaining in North Wales. Until, that is, we found a rogue John Rowlands living on a John Roberts farm in Wisconsin, neighbouring the other Rowlands'. His DOB fits the DOB for Thomas Rowlands brother, John. I did some digging around and find that this John Rowland's son and wife moved to the States and lo and behold there is another younger John Rowlands (call him John Jnr!) and his wife Catherine on another neighbouring farm.
John Roberts we think is Thomas's & John's nephew - son of their brother Robert Rowland!

TWIST three, However, as Roberts in not an uncommon name it's difficult to pin down and we think he may have gone over at a different time to our Rowland family. Wife name Jane + children.
Jude

If you followed all that - well done - I still have to have the notes out