The "Sister A Very Happy Birthday" card by Avant Garde is a beautifully designed folded card featuring a pink car and balloons, perfect for celebrating your sister's special day. The card is 18 cm in height and 14 cm in width, making it the ideal size to send a warm message to your sister. The card comes with an envelope for easy gifting and is artist-designed in the United Kingdom, adding a personal touch to the Happy Birthday theme.