Not sure what happened but my original message/responses (below). It was moved and parts deleted. Oh Well. Here it is again incase someone can help me find the death records, or newspaper notices. I have also added a few additional facts I found.
Thank You (and sorry for the long message)
Dan Harvey
Seattle

---Original/revised message posted 9 Oct 2009:
I am looking for any death/obit or other info that might be available for these siblings born on Prince Edward Island (parents Daniel McMillan and Mary McKinnon):

1.) Florence M. (Mary/May) McMillan b. abt 1879 on PEI and was buried at Mount Benedict catholic cemetery in Boston 21 Dec 1940. A Butler name was given in the cemetery record but I don't know the connection to the McMillan's. She was in Charlottetown, PEI in the 1901 Canadian census.
Additional Info: The Mt. Benedict cemetery said Florence lived at 62 Terrace St, Roxbury and plot pd by John H. Conway but don't know connection. The Mass. Archives Online Index had this info on Florence -
[Last Name First Name Town Years Volume Page Type]
McMillan Florence (Butler) Boston 1905 22 31 Death
I don't know anything about the Butler connection.

2.) Daniel J. (Joseph) McMillan/McMillen b. abt Apr 1878 on PEI and was buried at the New Calvary catholic cemetery in Boston 21 Dec 1940. I don't think he was ever married (per 1910 & 1920 census - couldn't find in 1930 census) but he did have a child out of wedlock (of the same name) that died 1 Oct 1902 and is buried in the Mt. Benedict cemetery, Boston.
Additional Info: New Calvary cemetery said Daniel lived on E. Dedham in Boston. The plot was pd by Minnie Beatty but don't know connection.

---Reply by jseni1952 posted 10 Oct 2009:
I tried checking for their deaths and could find any. I only found the death of Daniel and Mary Mcmillan's daughter Catherine Born 1878.