bcgenie_1,
This is a very challenging search and reconstruction, even for experienced researchers.
I viewed your tree data and put a comment on your tree about what I believe to be an error. There are same named persons, born in the same time frame, it's takes time and plotting geographically to insure you're following the correct line.
There are other inconsistencies I see in your tree (and other public trees) in particular the death data (record) for a Robert Blair. I believe you're citing this record in your tree, is that correct?
(source; familysearch.org "Wisconsin, Deaths and Burials, 1835-1968,"):
Name: Robert Blair
Gender: Male
Burial Place: Rosendale Cemetery
Death Date: 02 Nov 1883
Death Place: Rosendale, Fond Du Lac, Wisconsin
Age: 73
Birth Date: 1810 ***********
Birthplace: Scotland
Occupation: Farmer
Race: White
Marital Status: Married
Indexing Project (Batch) Number: B59602-3
System Origin: Wisconsin-EASy
Source Film Number: 1310183
Reference Number: 1964
The age of this Robert Blair you believe to be the husband of Adeline Chouinard is off by 30 years. Your Robert Blair is confirmed to have been born in 1840 and in Canada, therefore this is most likely NOT the death record for yours. Perhaps this Robert Blair is related in some manner, but he was not the husband of Adeline Chouinard.
I would venture record below might be a more likely suspect record to research, to rule in or out. The age and birth year of this Robert Blair are more consistent with the one you seek.
Name: Robert Blair
Gender: Male
Death Date: 26 Nov 1901
Death Place: Iron River, Bayfield, Wisconsin
Age: 65
Birth Date: 1836
Occupation: Lumber Scaler
Race: White
Marital Status: Unknown
Indexing Project (Batch) Number: B06541-2
System Origin: Wisconsin-EASy
Source Film Number: 1310172
Reference Number: cn 1274
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From the data I'm finding, I believe the Robert Blair/Adeline Chouinard family were definitely in Chippewa Falls, Wisconsin, probably immigrating there first from Canada after the 1881 Canadian Census. They appear to have only been in that area for a few years, they appear to have left that area by 1885. I see no evidence they were ever in the Fond du lac County.
There is enough evidence to assert the twin girls, Jessie & Lydia (listed by hrw30 above) were their children, as well as another record found for a Marie Louise, b 1882, and an infant (gender unknown) born and died in 1884, all in Chippewa Falls, Wisconsin. The fate of the twins is not known, however civil vital records for this period in Wisconsin are not comprehensive. The transcribed records on familysearch.org are solid in attribution of the mother, Adeline Chouinard. I don't see the name Jane Fowler, I see Adeline Chouinard in these records.
Another piece of evidence that places the family in this time period in Chippewa, Wisconsin is:
The eldest daughter, Marie Jeanne Elise "Jane" (b 1865), married Alfred Leduc in 1884 in Chippewa Falls, Chippewa, Wisconsin. That makes it highly likely she was in the company of her parents/family in that location in that time period. Again, the transcribed marriage record on familysearch.org has the mothers name, see below.
Groom's Name: Alfred Leduc
Groom's Birthplace: Canada
Bride's Name: Joanna Blair
Bride's Birthplace: Lathbiniere, Canada
Marriage Date: 06 May 1884
Marriage Place: Chippewa Falls, Wisconsin
Groom's Father's Name: Joseph Leduc
Groom's Mother's Name: Clara Grandmaitre
Bride's Father's Name: Robert Blair
Bride's Mother's Name: Adelina Choninard
Groom's Race: White
Bride's Race: White
Indexing Project (Batch) Number: M00343-8
System Origin: Wisconsin-EASy
Source Film Number: 1275831
Reference Number: p 258 cn 00935
Another interesting puzzle piece is that a son of Jane Blair (b 1865) and Alfred Leduc, "Louis Ira Leduc", (b 1888), states he was born in Cohoes, New York in his US WW1 draft registration. It appears his mother was in Cohoes for his birth, but returned to Wisconsin before the birth of the next child in 1891. All this kind of data can help you hone a specific timeline and location to look for more records.
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Another interesting find is the (son of Robert & Adeline) David Blair, (b 1876) signed up for military service in Canada in 1918. He gives his residence as Manchester, New Hampshire, and lists his mother, Adeline, as next of kin and as living in Manchester, NH. He states his martial status in 1918 as single.
Adeline's second husband, Edmond Blais, died in 1919 in Manchester, New Hampshire. (note: he was originally from the same locale in Quebec as Adeline). He is listed as married on his death record.
I haven't found Adeline in a 1920 Census, she is noted in the 1920 entry in the Manchester, New Hampshire City Directory, with her deceased husband, but is not present in the 1921 Manchester, New Hampshire City Directory.
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The obit of (son, Robert & Adeline) Albert J Blair (b 1868, d 19 Dec 1936), (your direct ancestor) states his sole surviving sibling is Hugh Blair of New Bedford, MA. This may or may not be true, but that's at least gives you an idea that all other siblings most likely preceded him in death.
Hugh Blair and "Euchre" (per the 1881 Canadian Census) are one in the same person.
It may well be true Adeline returned to Canada after the death of her 1st husband. I haven't found evidence of that in searching Canadian records from 1890 to 1905 that supports this. I've been looking for marriages or deaths of her children. Adeline connected at some point with Edmound Blais, obviously prior to marrying him in 1905. he appears to have immigrated to New Hampshire around 1893. I would track him further.
Family stories, especially of this vintage and passed down are not reliable, but can give you clues. The facts lie in the paper trail, some of which can be found on-line, some can't. You'll have to dig deeper than what is available on-line if you want to sort this out, that much I can advise. This is not an easy reconstruction, there was plenty of movement and that makes it a challenge to track, but there are all sorts of clues to your puzzle to find.
One of the obits I would try and find is of the eldest daughter, Jane (Blair) Leduc (b 1865). I tracked her last in 1930 in Virginia, St Louis, Minnesota, and it appears her husband may have died there in 1931. I didn't find a death record for her in Minnesota. I would suspect she went to reside with one of her daughters, one ended up in California (Alexina), but Laura remains MIA, I haven't figured out who she married, she was single and in the household of her parents in 1910.
See the documentation in the tree I posted a link to on another of your posts.