Hi Erica,
I went to the Perth Library but unfortunately there is no additional information on the Tainsh family.
As Throth states, in the pre-1855 MI’s of North Perthshire there is only the one reference to the name Tainsh.
All it says is
Block C 299 – ed. 1826; by Isabella & Margt Tainsh, to Fa, Mo, Bros & Sis.
There is nothing on the Tainsh family in W. Sievwright’s book Greyfriars Burying Ground.
In the supplement to the book (1895) there is this.
p.59 Tainsh. placed by Isabella and Margaret Tainsh, in memory of their father and mother, and their brothers and sister. 1826.