Brian Fairfax-Lucy wrote other books for children as well as these two pony titles (The Children of the House I can highly recommend). His full name was Sir Brian Fulke Cameron-Ramsay-Fairfax-Lucy, 5th Bt, and he was born on 18 December 1898, and died on 21 January 1974. His family owned Charlecote Park, now owned by the National Trust.
Finding the books
Horses in the Valley is now expensive with its dustjacket; the Scottie version is very difficult to find and so pricing does tend to be erratic. The Horse from India is not quite as easy to find as Horses in the Valley, but is usually cheaper.