Hi Dustyrover,
I must have had a "Peter Allen" Rio moment when I posted

Should have been;
James SCOTT, 21 December 1800, Abernethy, Perth, Scotland
Father PETER Scott
Try Famlysearch Pilot and check for other Christenings of Children to Peter Scott in Abernethy, Perth. This should give you a base time to search for a Marriage.
From what I can see, searched P S, All Events 1770-1810, Abernethy and came up with these;
Marriage;
Peter SCOTT
Christian DEWAR
22 August 1784
Only one I could find in Abernethy but Peters Wife may have been from elsewhere and Marriage took place there.
Children with Father PETER Scott;
PETER 26 Sept 1784
(MALE) Scott, Birth March 1785, Burial 30 March 1785
MARGARET 09 July 1786
NELLY 21 May 1786
WILLIAM 06 April 1788
PATRICK 16 Jan 1791
MARY 08 April 1792
ANN 02 June 1793
THOMAS 20 July 1794
ROBERT 20 July 1794
DAVID 28 Feb 1799
JAMES 21 Dec 1800##
HELLEN 13 Sept 1811
Hard to know if there was more than 1 Peter Scott Fathering Children in Abernethy
Sorry I cant be more help.
Other may have better ideas
