Ha Ha, that's something my hubby would do. It was actually just one of his sister's birthday, and if he brought that home, I would totally sign it and send it to her.
Actually, the story doesn't quite end there. He went out again and bought another (barely acceptable) one. It had a cartoon picture of someone on a beach with their trunks down, back view. He drew an arrow at the bare bottom and the words 'that's your face without make-up on, that is'. Inside he wrote 'Happy Birthday Pooface'. The card was delivered to my daughter's neighbours who opened it by mistake and brought it round. My daughter was mortified.