Margaret's great grandparents were George Lamb and Elizabeth Keith who married in 1774. They spent most of their lives in the Mains of Pitfour, Old Deer. Elizabeth died in 1802 and George in 1818. One of their sons, William, was born in 1777. He married Christian Keith in 1808. They were Margaret's grandparents. Christian was born in 1788, the daughter of Robert Keith and Isobel Rettie from Clackriach, Old Deer. Christian died in 1847 and William in 1854. Altogether William and Christian had eleven children: Isobel, my Christian, Anne, George, William, your Robert, Margaret, James, Mary, Elizabeth and Alexander.
I don't know of any photographs of the Lambs. Please feel free to get in touch if you think I can help you with any details of the family. The family gravestone is at Crimond.
Graham.