The 1911 census household transcript on Findmypast has:

Name, Relation, Condition /Yrs married, Se x, Age, BirthYear, Occupation, Where born

BEATTIE, William J Head Married M 50 1861 Tailor Douglas I O M
BEATTIE, Agnes Wife Married 25 years F 49 1862 Patrick I O M
BEATTIE, Lilian J Daughter Single F 19 1892 Domestic Servant Douglas Iom
BEATTIE, Joseph P Son Single M 16 1895 Barbar Assistant Douglas Iom
BEATTIE, May Daughter Single F 13 1898 School Douglas Iom
BEATTIE, Violet Daughter Single F 12 1899 School Douglas Iom
BEATTIE, Isabel Daughter Single M 10 1901 School Douglas Iom

RG number: RG14
Piece: 34665
Reference: RG14PN34665 RD635 SD3 ED18/12 SN108
Registration District: Isle of Man
Enumeration District: 18/12
Parish: Conchan
Address: 39 Allan St Douglas
County: Isle of Man

Using this information you can look up their marriage, bapts, and children's bapts/births on:
ht tps://www.familysearch.org/ [close space in ht tps]
and:
www.iomfhs.im/lawsons/LawsonBMD/Main_Site_index.html, which includes burials, census indexes, etc.
Six of their children's births are here: www.iomfhs.im/lawsons/LawsonBMD/births/ba_bir.html?Submit=Backwell+-+Bewicke .

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