Regarding Janet/Jessie, I rushed to think she was a sister of William and Jane and Mary and all the rest but she also could be an Aunt as possibly a much much younger sister of John's. Marriage to Catherine Sophia Hughs said to be 1844 so if Janet was born 1842, she may be sister to John or John's daughter with another earlier wife who likely would have passed-away. Another mystery. But in all, I do believe this record of death lines up with the date on William's gravestone and as noted she was from Queenstown.