Example: Author D is great granddaughter of M. M's 1st cousin marries My great grandfather's 1st cousin. Are we related? Are we 4th cousins "by marriage"? Where should I look for a definitive answer?
PID - person ID you find these next to the person's name in format with letters and numbers: XXXX-XXX
You can search for Arthur D or her great grandmother M in the Tree at: https://www.familysearch.org/tree/find/name
Once you open their person page you can click on View My Relationship:
I hope this helps
By most people's definitions, no, you're not related to Author D, but you are "connected" to her. By my count, it's 13 steps: you -1-> your parent -2-> your grandparent -3-> your greatgrandfather -4-> your great-great-grandparent -5-> your gggp's sibling -6-> that sibling's child -7-> that child's spouse -8-> that spouse's parent -9-> that parent's sibling -10-> that sibling's child M -11-> M's child -12-> M's grandchild -13-> M's great-granddaughter Author D. I suppose it can all be shortened to "4th cousins-in-law", although that implies a connecting marriage between siblings of the relevant ancestors, not between their first cousins.
Especially in smaller families, people do keep track of cousins-in-law, and many languages have words for some relationships by marriage (such as English "mother-in-law" etc.), but there's no formal definition, nor even a rule-of-thumb, for what "distance" counts as still being related.
Go to familysearch.org, then to the person/detail page of the PID of the person you want to see how you are related. On the top right click "View my Relationship". The diagram and the words just below the word Relationship and the person's name should help.
Non-definitive response: I responded earlier but then was confused and not sure that my response was correct. I don't think there is any 'relation through the marriage'. There may be some other relation which could be greater than 4th cousin (further back on both lines) but no 'relation through marriage' that I am aware of. There could also be some other relation through some other line but through the cited lines only the possibility of 5th cousin or greater. Perhaps referring to this cousin chart will help:
I will post a picture of what I would understand about your question shortly.
The picture may take a while to approve. Cousin to me means biological relation in this discussion.
If M's 1st cousin and your ggrandfather's 1st cousin marriage resulted in 3 descendancy generations - both you and Author D are 4th cousins to them separately but not to each other - one from the female side of the marriage and the other from the male side of the marriage.
You could possibly be 5th cousins or greater through the cited lines - or there could be some other relation through some other line between you both.
I have noticed FamilySearch Family Tree does - in 'View My Relationship' feature - indicate 'wife/husband of my __ cousin...' What does the Family Tree indicate your relation to Author D is? You can find this when viewing Author D's person page in the Tree and click 'View My Relationship' (upper right-hand side - across from image and Author D name). If Author D is living and not in the Tree - you can add the living relationships and connect them to the appropriate Tree relations - these people you can add would be in your Living Space and not be listed in the Tree for others to view.
Now - as to some other definition of 'cousin through marriage' - I am unaware (which I realize is your question). I hope this helps frame your question from my perspective accurately.
Thank you for your input.
Chas. Howell, can you tell me what a PID is? I tried to search a definition on the site and couldn't find anything specific. Personal Identification something? Clarification would help me a good deal. Thanks.
Thank you Julia. I appreciate your explanation.
Thanks Genthusiast. Your description and images of the icons definitely helps! I'm new to exploring FamilySearch and that helps a great deal.