1.Light music helps your baby easier fall asleep;Music may even help strengthen premature babies 2.Music plays a crucial role in "wiring" your babies' brain for learning. 3.Listening to music will help teach your infant about patterns and sequence, and about rhythm, beat and tone which are useful for problem-solving and reasoning 4.Early music exposure can help promote critical listening skills, language and literacy, creativity and coordination 5.To buy with ASIN-B00KFDQ1OG,it is the music box with 12 songs but without holder,perfect partner. Specification: The length of the bracket set(4 bracket set):22cm x 24cm,24cm,27cm,33cm The music box:12.0 x 6.7 x 2.5cm Package weight: 11.2 oz/318g The total height of the Baby Crib Mobile Bed Bell Holder:66.5cm Remark: Only music box without toys.To make you be able to personalize your baby's music box in a unique way he/she likes.If you need to buy one with more songs,pls search this ASIN-B00KFDQ1OG,it is the music box with 12 songs but without holder,perfect partner. What is included: 4Pcs Crib Bracket Set+One Music Box(Wind-up Music box with the song You are my Sunshine),Without dolls.