Regardless of whether they are left- or right-handed, human moms tend to cradle their babies on the left side of their bodies, especially in the early months. This left-handed bias likely has to do with the human brain’s lopsided layout: sensory information on the left side of the body is processed on the right side of the brain. The brain’s right hemisphere is also where emotions are processed, so holding and observing the baby on the left may help transmit social information to the right side more efficiently.