1891: 248 Hilltown, Dundee St Clement
Head: James DONEGAN 20, Jute Worker, b Scotland
Wife: Ann DONEGAN 20, b Scotland
Son: Thomas DONEGAN 6mths.
1901; 7 E Henderson Wynd, Dundee
Head: Agnes McARTHUR 28, b Dundee, occ: Flax ?eeler
Sister: Margaret KEEGAN ?6, b Dundee
Nephew: William KEEGAN 2, b England
Niece: Margaret KEEGAN 8mths, b Dundee
Sister: Ann DONEGAN 30, b Dundee, occ: ?--- ?----er
Nephew: Thos DONEGAN 10, b Dundee
Nephew: Alex DONEGAN 9, b Dundee
Scotland's People list 2 Agnes McArthur DONEGAN deaths
1) 1894, age 0, Registered St Peter Dundee
2) 1900, age 0, Registered St Peter Dundee
So unless you have sure knowledge to the contrary, it does look as if both the same-name girls died as infants.
Cheers
AMBLY