I think I may be able to help. John McComb Maitland from Milngavie was my great grandfather. He was married to Annie Wilson. They had 3 children, the eldest John Wilson Maitland, borm c 1910, then David Flockhard Maitland (my grandfather) born 1912, and finally Marion Maitland (known as Minnie) born c 1914.
John McCombe Maitlands father was indeed Daniel Maitland born c 1857 Milngavie Occupation: Stoker (1877) (1908) Laundry fireman Residing at: 1877 Highland Row, Milngavie (at marriage) 1881 Walker's Land, Cheapside, Milngavie. 1901 6 Hillhead, Milngavie. 1925 19 Main Street, Milngavie Died Western Infirmary 17/1/1925 aged 68
who was married to Annie McComb born c 1853, Milton of Campsie, Stirlingshire.
From the info I have, they had at least another 3 children Margaret McComb Maitland b 1882 Annie Maitland b 1884 Jessie Stewart Maitland b 1888.
Daniel Maitland (1857) had another 4 siblings I know of. John Mitchell Maitland born c 1855, James born c 1860, Duncan born c 1863 and Archibald born c 1866.
Their parents were James Maitland born c 1835, and Mary Mitchell born c 1833 (died May 22nd 1872). He then remarried as you said a Mary McLean in 1873.
James Maitland's parents were Daniel Maitland and Jean Buchananborn c 1800-1810, so these are indeed the later Daniel's grandparents!
I have loads more info, but it's hard to put down on paper. Maybe you would like to get in touch as it looks like we are both working on the same lines?