1861 census, Carstairs (from a transcription)
George Martin, 62; wife Agnes, 62; daughter Helen, 38; grandchildren George Hamilton, 18; William Martin, 4 and Anne Martin, 4, all born Carstairs.
The 1851 census says that George was born in Dunsyre.
George Martin, aged 82, died in Carstairs in 1881. Have you seen his death certificate? What does it say the names of his parents were?
Agnes Donald or Martin, aged 72, died in Carstairs in 1870. Have you seen her death certificate? What does it say the names of her parents were?
If you have not already seen these death certificates, I recommend that you go to Scotland's People
www.scotlandspeople.gov.uk and do so now.