My mom just loves my blenheim spot - sometimes she leaves lipstick on it. That's not as bad as the time I chewed on a sharpie and colored my head and paws green! I read somewhere that a queen was rubbing her cavie on the head to comfort her when she was having puppies, and she left a thumb print- a blenheim spot!
Faolan has a "kissing spot", too. I read about the same story of the english woman who rubbed the head of her pregnant female cav with her thumb. She was worried because her husband was at war at Blenheim. The legend is that all the puppies were born with the thumbprint or "Blenheim spot" on the top of their heads the next day. Interesting, huh?