Marion Ritchie and the Renwick family

The bottom of this gravestone can no longer be deciphered and I'm indebted once again to Sheila A. Scott's book Peeblesshire Monumental Inscriptions-pre 1855 for the details of the last person mentioned. Here is the full text from the top:

Erected

by

John and Archibald Renwick

in memory of

Marion Ritchie, their Mother

who died 13th January 1845

aged 62 years

also

William Renwick their brother

who died 1826 aged 6

also

Thomas Renwick

died 1863 aged 85.

I strongly suspect Thomas Renwick was their father and the husband of Marion although I don't know for sure as moss has covered the actual inscription at the bottom.