I do have a bit more on Henry Francis McCullagh's family but still lots of gaps.
Henry/Harry Francis McCullagh (27 June 1841-16 Dec.1916) m.1 (14 Sept.1864 Errigal Parish Church) Charlotte Cash (1844/1847?-10 Dec.1875 “Sea View Lodge,” Belfast), teacher. He m.2 (c1885) Mary Skates (c1861 Co.Down-aft.1911).
1.
Letitia Margaret McCullagh (12 Aug.1865 Garvagh dist.).
2.
Caroline McCullagh (10 May 1867 Garvagh dist.) m.(27 Mar.1895 Newtownards) John McClune.
3.
Charlotte McCullagh (17 Feb.1869 Belfast).
4.
Henry Francis McCullagh (11 Jan.1871 Belfast-?8 June 1941).
5. Ethel McCullagh6.
Mary Louise McCullagh (1885 Belfast).
7.
Georgina Elizabeth McCullagh (3 Oct.1887 Belfast) m.(1913 Belfast) Joseph Crawford Hill.
8.
Florence Edith McCullagh (6 July1889 Belfast-aft.1901).
9.
Alexander McCullagh (29 May 1891 Belfast-aft.1901).
10.
Clara McCullagh (11 Apr.1893 Belfast-aft.1911).
11.
Sarah McCullagh (c1896 Belfast-aft.1911).
?12.
Frederick McCullough (27 Oct.1896 Belfast-?26 Jan.1897 Belfast).
?13.
Kerby? McCullagh (c1909 Belfast-aft.1911).
Ethel McCullagh (20 Nov.1873 Belfast-?17 May 1934 Belfast) m.(24 Apr.1905 St. Mary Magdalene Church of Ireland, Shankill Parish, Belfast) Thomas Neill (d.aft.1911).
www.census.nationalarchives.ie/pages/1911/Antrim/Cromac/Laganvale_Street/1652141.
Henry Francis Neill (July/Sept.1908 Auckland dist., Durham, Eng.-aft.1911).
2.
Margaret “Maggie” Neill (July/Sept.1910 Auckland dist., Durham, Eng.-aft.1911).
3.
Thomas Neill (25 Aug.1914 Belfast)- mother McCullagh.
4. Son (stillborn 13 Dec.1919). City Cemetery (public ground)- child of Thomas & Ethel Neill, 37 Laganvale St.
5. Ena Neill.
6. Billy Neill.
Hope this helps. If you can fill in any recent details send me a PM so that we can exchange email addresses.