I don't know about 1881 but in the 1891 Census there is a Robert McWatt, born in Manchester, age 19, and living in Chorlton. He was newly married to Sarah Jane, age 18, and they were living with her widowed mother Marion, or Marian, Kirk and younger sister Drusilla Kirk. The Kirks were from Bradford, Yorkshire - Marion was born Mary Ann Webster and in 1871 her brother Jeremiah (my great-grandfather)was lodging with them in Bradford. I have information on some of their McWatt descendants, but I am seeking more details on the Kirk sisters (there were 4 altogether.)