Annie married George in 1899: Geo WHYATT to Annie HARRISON Reg. year1899 Reg. no831
Births, a couple you haven't mentioned also included:
HARRISON Beatrice Eleanor Father's name Unknown Mother's maiden name Annie (Harrison) Reg. year 1891 Reg. no1491
HARRISON Myrtle Harriet Reg. year1893 Reg. no1085
HARRISON Edith Elizth Reg. year1896 Reg. no15744
HARRISON Arth Roechner Reg. year1897 Reg. no22896
WHYATT Fran Stewart Geo Annie (Harrison) Reg. year1899 Reg. no11181
WHYATT Percival Jas Geo Annie (Harrison) Reg. year1900 Reg. no19597
WHYATT Zero Herbert Geo Annie (Harrison) Reg. year1901 Reg.
WHYATT Matda Ellenor Geo Annie (Harrison) Reg. year1902 Reg. no29662
WHYATT Billy Bell Geo Annie (Harrison) Reg. year1905 Reg. no5914
WHYATT Jack Albert Unknown Annie (Harrison) Reg. year1906 Reg.
WHYATT William Bell Unknown Annie (Harrison) Reg. year1910 Reg. no7452
Possible Annie's death: Reg no. 10530 Reg year1961
WHYATT Annie Father's name HARRISON Mother's name Unknown (Unknown) Place of birth: HORSHAM Place of death: WARRNAMBOOL, age 84
Zero died 1902, Matilda and Percy 1904 and Billy Bell 1905, Henry Francis Stewart 1984
HARRISON Arthur Recheoner Father's name John Arthur HARRISON Mother's maiden name Annie (Recheoner) Reg. year1974 Reg. no21094
Arnott Edith Elizabeth Father's name / Spouse's family name WHYATT Mother's maiden name Annie (Harrison) Reg. year1961 Reg. no22044
Jane's birth: HARRISON Jane Thomas and Mary Jane (Trotter) Reg. year1875 Reg. no15331
Annie's birth mistranscribed. Was she Jane's twin?: HARRESON Annie Thomas and Mary Jane (Trotter) Reg. year1875 Reg. no22334
GOULD Louisa Albert Edwd and Mary Jane (Youngtrotter) Reg. year1880 Reg. no1861
GOULD George Albert Albert Edward and Mary Jane (Young) Reg. year1882 Reg. no8608
GOULD Susannah Amelia Albert Edward and Mary Jane (Youngtrotter) Reg. year1884 Reg. no19174
GOULD Francis John Albert Edward and Mary Jane (Youngtrotter) Reg. year1886 Reg. no28342
GOULD William Edward. Albert Edward and Mary Jane (Youngtrotter) Reg. year1889 Reg. no17581
GOULD Flor Hope Albt Edwd and Mary Jane (Youngtrotter) Reg. year1891 Reg. no18414
GOULD Albert Edward HARRASON Mary Jane Reg. year1879 Reg. no281
GOULD Albert Edward YOUNGTROTTER Mary Jane Reg. year1879 Reg. no281
William Edward Gould's death notice 1939, 1st column, mentions all siblings other than Annie. It also give married names of the girls.
http://nla.gov.au/nla.news-article11236228Jane's marriage: Jane HARRISON to Wm Jonas BENNETT Reg. year1897 Reg. no2390
Jane's death: Jane BENNETT Alfred HARRISON and Mary Jane (Young-Trotter) Reg. year 1953 Reg. no21701
Jamjar