Hi Rik,
I deleted the first response to your question as I noticed a very grave error on the part of Justine Chenell who gave me this information. She gave Annie's husband as Harry Chenell, son of David & Emily (McPhail). However, if this were true, he'd only be four years old at the time of Annie's death in 1916 (he being born in 1910).
I did find something else in my notes however to help you.
Albert Chenell, son of Benjamin & Matilda (Collins), married an Annie Clarke (most possibly your daughter of Jabez and Nancy (Nancy Maria Keating) on PEI circa 1906-1907. Since you live only across the Strait, you could probably check this out at the Provincial Archives in Charlottetown when you have the time and let me know what you find.
Albert and Annie had a daughter Alice, born at Athol, MA in 1907. Annie died in Boston on 15 May 1916 and was later buried at Grosse-Ile on 2 Jun 1916 (according to the Grosse-Ile registers).
Albert & Annie may have been divorced because they were not living together in the 1910 census; their daughter, Alice E, 2 years old, is living with her Chenell grandparents in Beverly, MA. And also because Albert remarried in Halifax, NS on 7 Sep 1915 (year before Annie's death; record states he was a bachelor) to a Margaret Peters, daughter of James & Betsy (Clark). Albert & Margaret had a son Donald, who witnessed the aftermath of the murder/suicide of his parents in Halifax of April 1937, as you already know. A terrible tragedy.
This should be of help to you.
Best regards, Dennis