There has been constant debate about whether co-sleeping is beneficial or harmful to children's development. But studies have shown that co-sleeping with the parent influences the emotional development between parent and child. By sleeping together with the parent, the warmth of his body, in addition to the sense of protection, allows attachment between the two. The baby is able to follow the parent's breathing rhythm even while sleeping together. Exposure of children to toxins in their parents' breath also aids development. Furthermore, co-sleeping has been observed to have prolonged effects on social interactions between parent and child. The purpose of this article is to examine how co-sleeping is beneficial to infants' development. One of the issues with most parents of newborns is how much sleep their baby gets and when the sleep occurs, whether during the day or at night. An important goal for parents is to eliminate the stress of their children's night waking by encouraging them to acquire early, healthy and independent sleep habits. This is the goal of most parents, especially in Western countries like the United States, which is why many are against co-sleeping. Sleeping through the night or settling down is a misleading concept. Most adults and children wake up periodically during the night and fall back to sleep without being aware of these awakenings, something that newborns cannot achieve immediately. Parents of newborns cannot expect the baby to have eight hours of uninterrupted sleep, especially in a room alone, but they can expect gradual improvement. Wolfson, Lacks, and Futterman (1992) study the effects of parent training on children's sleep patterns, parental stress, and perceptions of parental competition...half of the article...nt, if not more important, than bedtime practices in predicting infant sleep quality (Teti et al., 2010). The findings support the theoretical premise that parents' emotional availability to infants in the context of sleep promotes feelings of safety and security and, consequently, better regulated infant sleep. In conclusion, although none of the above directly states how co-sleeping affects emotional development in infants it is evident that infant sleep is extremely essential to overall infant development. During the moments when children sleep with their parents, they have a lot of availability from their parents which will calm them down when they go back to sleep. In turn, this improves parent-child attachment, which will influence how children show their emotions. Being able to express their emotions freely and having a responsive parent will be beneficial to their emotional development.