Views about the father of these Blues, please

[Shona]

Rebecca Blue was born on the island of Colonsay. She never married, but had at least six (possibly eight - see note at end) illegitimate children, all before statutory registration. None of the births appear in the baptismal register for the island. These are the children that I've identified from census and other records:

- Mary McNeill, born c1822
- Ann McNeill, born c1827
- Catherine ??????, born c1833
- Neil McPhyden, born c1835
- Iver Blue, born c1838
- Duncan McPhyden, c1841

The only reference I have for Catherine is on the 1841 census - her surname is Blue. However, all the other children have the surname Blue on that census record.

This is the information I've gathered about the fathers.

1860 Marriage of Ann McNeill to Alexander Black
Father: Alexr McNeill.

1862 Death of Iver (English = Edward) Blue
Father: Duncan Blue, labourer (dec).

1864 Death of Mary McGlary
Father: .........McNeill, farmer.

1901 Death of Neil McFadyen
'Illegitimate fisherman...Duncan McFadyen reputed father, ploughman, dec.'

1907 Death of Duncan McFadyen
Father: Duncan McFadyen, ploughman (dec).

Are there three fathers - Mr McNeill, Mr Blue and Mr McFadyen? Or could it be Duncan Blue is actually Duncan McFadyen?

I can find Duncan McFadyen, ploughman, on the 1841 and 1851 census records - with his a 'wife' (no marriage record, though) and children. No sign of a Duncan Blue of the right age.

There was large-scale emigration to Canada (forced, 'encouraged' and voluntary) in the first half of the 19th century, so the fathers may have been long gone.

NOTE
1851 Census - Greenock
Alexander McNeill, head, 28, weaver, born Colonsay
Mary McNeill, wife, 30, born ??? Argyll
Rebecca McNeill, daughter, 7 months, born Greenock
Dugald Blue, visitor, 25, cooper, born Colonsay

Wondering whether Alexander is also one of Rebecca's children, given that his daughter is named Rebecca. Also what about Dugald Blue?