1st Birthday Party Supplies, Party Favors and Party Decorations. It is customary in many cultures to celebrate the anniversary of one's birthday, for example by having a birthday party with family and/or friends. This is especially true of one’s First Birthday. A birthday is considered a special day for the person, and so the person will often get special treatment from friends and family. Gifts are often given to the person celebrating the birthday. It is also customary to treat people specially on their birthday, either by wishing them a “Happy Birthday” or giving them a gift. You will find a large assortment of 1st Birthday party products including invitations, cups, plates, napkins, banners, party favors, stickers and more. Create an unforgettable birthday party for your little one with our full selection of 1st Birthday party supplies.