Your Donaldsons were in the Braddan records.
Braddan Burial Records

Ann Donaldson age 46 residence Douglas buried 15 Sep 1865 grave 1707

Catharine Donaldson age 68 residence Douglas buried 19 Oct 1863 grave 1198

David Donaldson age 65 residence Onchan buried 4 Jan 1885 grave 1707

David Alexander Donaldson age 67 residence Douglas buried 11 Jul 1916 grave 1707

James Donaldson age 49 residence Onchan buried 26 Aug 1894 grave 1707

Sarah Jane Donaldson age 17 residence Douglas buried 7 Dec 1863 grave 1707

William Donaldson age 32 residence Douglas buried 16 May 1876 grave 1707

No Braddan Monumental Inscriptions for them.
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The only Onchan Donaldsons are
John age 91 died 3 Aug 1861 and Mary age 82 died 18 Sep 1883
Sacred to the memory of John Donaldson who died Aug 3 1869 aged 91 years
Formerly Capt and ship owner of Liverpool
also to Mary relict of the above and daughter of the late Peter McClcaren of Edinburgh who died on the 18th day of September 1883 aged 82 years