As I see things, a timeline runs like this:
23rd June 1883, birth of Thomas Richard Keig, to Thomas Keig/Emily Clarke
29th November 1885, birth of Emily Margaret Keig, to Thomas & Emily
4th April 1887, birth of Walter Keig, to Thomas & Emily
11th November 1888, birth of Willie Keig, to Thomas & Emily
22nd March 1889, burial of Emily Keig
31st October 1889, marriage of Thomas Keig to Eleanor Gale
4th September 1890, birth of James Herbert Keig, to Thomas Keig/Eleanor Gale
So, the 1891 census shows:
Reference RG12, Piece 4692, Folio 52, Page 21
Fistard, Rushen
Gale, Eleanor Wife F 39 Fisherman's Wife
Gale, Annie Daughter F 10
Gale, Thomas Son M 7
Gale, Eleanor Daughter F 7
Gale, Emily Daughter F 5
Gale Walter Son M 4
Gale, James Son M 7 months all born Rushen
The last 3 children correspond to births mentioned above.
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14th August 1897, birth of Frank Keig, to Thomas Keig and Eleanor Gale (dec'd)
24th August 1897, burial of Eleanor Keig, age 45
26th October 1897, burial of Frank Keig, age 10 weeks
6th February 1898, marriage, Thomas Keig to Margaret Pirrey
31st July 1898, birth of John Robert Keig to John Thomas Keig & Margaret Piercy
Census of 1901:
Reference RG13, 5305, 46, 8
1 King Street, Onchan
Gale, Thomas Head M 41 Fireman on Steamship b Rushen
Gale, Margaret Wife F 40 b Andreas
Gale, Walter Son M 14 Butchers Apprentice b Rushen
Gale, William Son M 12 b Rushen
Gale, James H Son M 11 b Rushen
Gale, John R Son M 2 b Douglas
Piercy, Amelia Step Daughter F 12 b England
And again, all the children mentioned here seem to tie up.
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So, I can't see that you've made any assumptions that aren't correct!
And I can't understand why Thomas kept the surname Gale?
Maybe it was to do with inheritance and property?
I know that women inherited property/land under Manx law - maybe he kept hold of some land/property as long as he kept Eleanor's surname?
Just guessing here - maybe a proper Manxie will have a better idea?