The doll can be placed with or near the child to give a feeling of closeness and comfort and to help the child fall asleep as well as stay asleep. Keep the doll close to your skin before giving it to the child. That way the doll can absorb your scent to give the child an added feeling of comfort and safety. For children under 12 months it is recommended to keep the crib bare and rid of soft bedding, including crib bumpers, blankets, pillows and soft toys. The Lulla doll can be attached to the outside of the crib for children under 12 months and the attachment straps are located in the pocket on her back. The real life sounds alone can help children feel stable and safe, adding to the quality of sleep and wellbeing.To turn on the sound press the heart shaped speaker button on the sound-unit for 3 seconds. The sound turns off automatically in 12 hours but you can turn it off sooner by pressing the heart shaped button for 3 seconds again. The 12 hour timer resets every time you push it off/on.Adjust the volume by pressing the button on the side of the sound unit. It has three volumes and the highest is a safe 65 dB making it safe for prolonged use for children’s sensitive hearing.  When the sound is turned on it always starts on the lowest volume.You can also turn on the sound and adjust the volume once you placed the sound unit inside the doll. We recommend placing the sound unit forward facing inside the doll and then you can press on the heart of the doll to turn her on/off and under her left arm to adjust the volume.The sound unit uses two AA batteries. You can use both alkaline and rechargeable. Do not use Lithium batteries. Please note that rechargeable batteries can be bigger in size and some brand types might not fit the sound unit. Good quality brands that do fit the Lulla doll sound unit are for example Eneloop and Ikea rechargeable batteries.