Home / Twisty / Doc I Keep Hearing Strange Voices In My Underpants! Birthday Card Doc I Keep Hearing Strange Voices In My Underpants! Birthday Card£3.49 Card Size: 5” x 7”. Blank Inside. Envelope Included. Funny Birthday Card. 6 in stock Doc I Keep Hearing Strange Voices In My Underpants! Birthday Card quantity Add to basket Related products Father’s Day Card For My Old Man Sit Back And Relax £3.49 Add to basket Fully Qualified Grumpy Old Git Birthday Card £3.49 Add to basket Banned From The House Of Lords Rude Birthday Card £3.49 Add to basket Fake News Birthday Card £3.49 Add to basket