Ontario birth records after 1909 are protected by privacy laws.
The 1908 passenger list is for a different McCann family. I found the marriage registration for Louis John McCann to Catherine Greenshields and his parents were John McCann and Ann McKay.
However, Kathleen's parentage does still have to be questioned since she would have been conceived approximately 15 months before Jerry and Nellie were married.
The 1911 death registration does says Nellie was born in Scotland and it is definitely the same family on the census as the addresses match on both the death registration and the census (86 Caroline Street). As you will see from the information below, I found that John and Ellen were born in Ireland but their children in Scotland so likely the enumerator assumed a birth place of Ireland for the whole family.
According to her birth registration, Martha McCann was born 18 Feb 1904 in Paisley, Renfrewshire to John McCann and Ellen McCafferty. John and Ellen were married 10 Sep 1878 in Paisley. James McCann was born 3 Apr 1900 in Paisley. The address on both birth registrations is 28 Newton Street, Paisley.
I looked for a McCann family on the 1901 Scotland census and found the following one living at 28 Newton Street, Paisley:
John McCann, head, 45, Ireland, general labourer
Ellen McCann, wife, 41, Ireland
Mary McCann, daughter, 21, Paisley, laundress
Susan McCann, daughter, 20, Paisley, cotton millworker
Ellen McCann, daughter, 19, Paisley, cotton millworker
Catherine McCann, daughter, 17, Paisley, cotton millworker
Alice McCann, daughter, 15, Paisley, cotton millworker
Margaret McCann, daughter, 14, Paisley, cotton millworker
John McCann, son, 11, Paisley
Annie McCann, daughter, 9, Paisley
William McCann, son, 7, Paisley
Elizabeth McCann, daughter, 6, Paisley
Marion McCann, daughter, 4, Paisley
James McCann, son, 1, Paisley
I have found a passenger list entry for John McCann and his daughter Catherine arriving in Montreal on 10 Jun 1903 aboard the Corinthian so the timeline fits for Ellen becoming pregnant just before John went abroad. Here's a link to the image at Library and Archives Canada (near the bottom of the page):
http://data2.collectionscanada.gc.ca/e/e147/e003653937.jpgI can't find an entry for when the rest of the family joined them.
Jacquie