Hello Adrian,
The 1901/1911 census returns include reference to DED’s (district electoral divisions) which are small administrative areas. Roskeen is shown as being in Newport West and whilst no Loftus family are recorded here there are Loftus families in the townlands of Bunnahowna, Drumfurban, Glennamaddoo, Murrevagh, Rosgalliv, Mallaranny and Newfield all of which are in the DED of Newport West.
Assumptions may be made that she was born before the 1911 census and lived in Roskeen prior to her arrival in Dublin. Whilst the latter may be true she may be from a line from one of the other townlands having moved after the last census and as we all know you do not have to be 16 and over to conceive a child.
I would suggest you research the aunt with whatever details you have which hopefully will lead you back to the Loftus connection in Newport West as her history should be less shrouded in secrecy . If successful you will find Rootsireland have parish records for Burrishoole/Newport upto 1920 and you may also need to consult the Civil Records for the registration district of Newport.
As an indicator there was a baptism of an Anne Loftus, address not given to the parents John Loftus and Bridget Sweeney June 1 1913, though this may be unrelated in the Roman Catholic Parish of Burrishoole/Newport.
