Taking child Henrietta (not so common a forename), there is a record for a Henrietta Wilson born in 1899 to William Wilson and Rebecca Kerr in Belfast, critically, William is is described as a butcher, which ties in with the 1901 census.
Moving back, there is a marriage for William Wilson to Rebecca Jane Kerr on 12 July 1888 in Crescent Presbyterian Church Belfast, he is listed as a flesher's assistant, again tying in with the other records. I know this marriage date doesn't gel with the stated no. of years in the 1911 census, but since son Thomas (born 1890'ish according to the census records) seems to be nearly, if not the oldest child, I'm assuming the 28 years married which is stated in the 1911 census is wrong.
BTW, the marriage record shows that William Wilson's father was Thomas Wilson, a cattle dealer, Rebecca Jane Kerr's father was George Kerr, a labourer.