Hi Heather, found peter Menzies father on 1851 Scotland Census, info as follows:
Janet Menzies, daug, age 2, Midlothian,
John Menzies, head, age 40, joiner journeyman, Dull, Perthshire,
John Menzies, son, age 12, midlothian
Rachel Menzies, wife, age 36, midlothian,
living at Mino Park
I know...