If you mean that you have a paper trail connection and want to know if DNA testing will confirm links the answer is yes definitely.
I manage several DNA tests on Ancestry and trees for relatives and friends .
+ Have solved questions about parentage of ancestors & descendants of half siblings . Beyond 3rd cousins it gets harder ..but definitely worth doing . I don't have experience of other sites but am about to download my ancestry results to My.Heritage and GED match
Look forward to seeing if they give more connections.
Sutton : Many people think DNA only helps identify close relationships and don't realise that it can prove your connections to 5th great grandparents
I helped my 3rd cousin work out his birth father by comparing our mutual matches .he was closest to a 2nd cousin on my maternal grandfathers side then we worked out who his 1st cousins & my other 3rd cousins were .
But it's not easy and you may need help from someone who knows how to compare your matches .
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