This 5-piece Cocomelon set is perfect for your child's next birthday! You can select a pkt or helium gas-filled balloon for a fun addition to any party. Let your little one celebrate with their favorite characters and add a touch of magic to their special day. Floating Time (Helium)The foil balloons, filled with helium, will stay full for 2-5 days. They may float for longer but will start to appear more deflated as they lose helium.