The second marriage and children to 1875 (when the online IGI extraction stopped) is as follows:
DONALD MC GREGOR / MARION HOWDEN
Marriage: 15 FEB 1867 Edinburgh Parish, Edinburgh, Midlothian
DONALD MC GREGOR - Birth: 26 OCT 1867 Edinburgh Parish, Edinburgh, Midlothian
MARION MC GREGOR - Birth: 26 MAR 1869 Edinburgh Parish, Edinburgh, Midlothian
ANDREW WEBSTER MC GREGOR - Birth: 28 AUG 1870 Edinburgh, Midlothian
DUNCAN MC GREGOR - Birth: 28 OCT 1872 Edinburgh, Midlothian
According to one of the messages above, there is no sign of young Donald in the 1871 census. Had he died young?
ADP