I'm confused about Mary, Edith and Sybil's ages. Their pages say they were born in 1890, 1894 and 1897, respectively, but I don't think that's right. I was reading the official companion book to Downton Abbey the other day, and it said that Sybil was 17 when the show began in 1912, meaning she would have been born in 1895. Furthermore, Julian Fellowes wrote that Mary was inspired by one of his ancestors, a grandmother or great-grandmother or something, who was born in 1880, making her "more than 10 years older than Mary" (my paraphrase). Then, in 1x07 (which is set in 1914), Rosamund says that Mary has had four Seasons. I know basically nothing about Seasons or debuts or anything like that, but isn't a young aristocratic lady presented to society when she's 18? Which would mean Mary was probably born in 1892, not 1890. (I haven't mentioned Edith because I don't recall if they said anything about her age, either in the book or show.)
Anyway, I changed Sybil's birthyear to 1895, but I thought the whole community should decide whether or not to change Mary's date of birth. So what do you think? Does 1890 sound about right, or is she a bit younger than that?