How could we be related. All combinations make zero sense

Question

I the poster is K2 as related below

Objective:

Learn how T and G fit into the K's tree T&G appeared in DNA match with CM to K2 (K1 is still in testing)

BackGround

T and G are siblings born in the mid 47 and 57(Their parents were born in 1921) K and K2 are siblings born in 66 (Their parents were born in 43 and 44)

K2 and T match 971 CM across 35 segments.

K2 and G match 828 CM across 33 segments

K2 and CB who is G's daughter matches with 307 across 15 segments

According to DNApainter they say with 100% certainty that K2 and T's relationship is one of the following. The probability only drops to 96% for the same relationship status between K2 and G.

Here are the possible combinations according to DNApainter and my (K2)'s explanation as to why this wouldn't make sense. And input is much appreciated. What am I missing??

Great Grandparent or Great Grandchild possibility = That can’t be, were only 19 years apart.

Great Uncle/Aunt or Great Niece/ Nephew= Again for that be true the T and G would both have to be siblings to K and K2 grandparents. Again, K and K2's grandparents were born between 1908 and 1924. Again, extremely unlikely in my opinion.

Half Aunt/ Uncle or Half Niece Nephew. = That would require you both to be half siblings to either one of K and K2’s parents. K and K2’s parents were born in 43 and 44. Or that K and K2 both are half siblings to T and G’s parents. T and G’s parents born in 1921, K and K2 born in 66.

1st Cousin= That would require one parent from T and G to be a full sibling to one of K and K2’s parents. Again, since both 2 sets of parents are 23 years apart, I find that extremely doubtful.

Additional info To be clear I (K2) DON'T recognize anyone on shared matches with T or his sister G. I do have known DNA matches myself, these matches are My dad’s 1C This person would be my Dad’s Mom, Brothers son. That would make him to me 1C1R

Next known connection for me. This person is my Dads 1C. This person would be my Dads Moms Sisters son. That would make him to me 1C1R

Next know is a 2nd cousin. She is the daughter of the above referenced 1C1R

Next known connection is a 2nd cousin. His Dad and my Mom are 1st Cousins. These 2 first cousins, mothers are sisters (My Mom and his Dad)

None of these known people match anyone from T and G or shared matches.

So “ If I understand this”. The connection to T and G for me HAS TO BE on my Moms Dad side or on my Dads, Dad side. I say that because I have cousins that don’t match T and G from my Dads Mom side and my Moms Mom side. Is that correct?

So I presume having my Moms DNA tested should either say its her and her Dads side, or she will not make a connection to T and G , then by deduction it will have to be my Dads Dad side that T and G fit into. Is that correct??

Assuming my Mom isn’t a match for T and G, would having a DNA test on my Dads 1C , the relation would be my Dads, Dad, Brothers son

Would that help answer where T and G fit in? , if the connection isn’t on my Moms side

Unfortunately, the older generations are dying off quickly.

Answer 1

You likely can't tell with just the information you've provided. And you most certainly won't be able to conclude anything.

Are there any others who have tested that share DNA with T and G where you know how they're related to K2? If so, you can use that information in the What Are The Odds? (WATO) tool that also happens to be at the DNA Painter site.

With it, you can build your hypothesized family tree that include K2 and the other known relatives of K2, and enter their centimorgan relationships with T into the tool.

Next, place T into the tree at various places where you think the relationship might be, and the tool will tell you whether that relationship is plausible and if more than one is, what their likelihoods are relative to each other.

Since you'll have different centimorgan relationships with G, you can simply do it again with G's values (since they are siblings) and the results should somewhat agree, remembering that siblings do get difference parts of their parents' DNA.

The diagram below is from an article by Leah Larkin (The DNA Geek) about the WATO tool showing an example with 9 hypotheses:

The WATO tool makes use of the same probability tables that the DNA painter Shared cM tool does, so WATO could tell you what you might be missing.

However, you do need that extra information of at least one other known relative of K2 who is DNA related to T and G. If you don't have that, you should see if there are any cousins on the suspected side that you can ask to get DNA tested.