Mother Webber was probably Maria L. (Taggart), widow of Brooks K. Webber of Company I (16th NH). They had a son named Bernard born 1895, who may be the young man in the third row centered between flags. Brooks died in 1903, so this photo may in 1910's, based on Bernard's age in picture.
Andrew "Andy" Holt, a sergeant in Company G, was a Lyndeborough resident. His wife was Abby J, whose obituary mentioned she was a member of the Woman's Relief Corps, and she died in 1916. Andy passed away in 1924.
John C. Carkin was also a Lyndeborough native, and he had served in Company H. He died in 1923.
The New Hampshire Veteran's Association was originally made up of Civil War veterans, and was formed in 1875 (in Manchester, NH). Their second reunion was held at Weirs Beach (or The Weirs) in 1878, where they continued to hold their encampments in the decades to come. Land was donated the following year, and buildings were constructed to house the veterans of the individual NH regiments.
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