Hello had a look for your Holmes family
If the birth of William is correct I can see four other siblings
Sarah Holmes 1836
Joseph Holmes 1838
Mary Holmes 1840 (mothers name not given)but same townland
William Holmes 1843
Catherine Holmes 1845
Father Andrew Holmes, mother Rebecca Allen, births registered Raphoe Presbyterian church
Address for first three births, Lismontigley, Raphoe
on Catherine's birth the address is given as Milltown, Raphoe, a John Holmes is listed living at Milltown in the Griffith Valuation of 1858.
Interestingly on the transcription of Williams birth it does state that Andrew Holmes was a Church minister, I don't see any other references to an Andrew Holmes Minister and occupation is not given on other births so a bit dubious
Hope this helps