I love Thelwell! I've owned a copy of his "A Leg at Each Corner" for many years, and it still makes me laugh my head off every time I read it and look at the wonderful illustrations. I strongly recommend it for anyone with young daughters who love horses.
Rather posh professional-class mum in the door of the sitting room - "Well! That's the LAST time I let you have friends over to watch the International Horse Show!"
Five or six kids sitting on ponies, all watching the TV and cheering, waving hunting crops around, etc. Ponies in the easy chairs, front feet up on the ottomans . . .