asÂ·soÂ·ciÂ·aÂ·tive property. The property of addition and multiplication which states that a difference in the grouping of numbers being added or multiplied will not change the result, as long as the order of the numbers stays the same. For example, 3 + (4 + 5) is equal to (3 + 4) + 5. See also commutative property, distributive property. 1  Facebook.
The most common recommendation is to initially place infants to sleep on their backs for the first 12 months. However, when the infant is able to roll over on their own in to the sleep position of his/her choice than it is fine to leave the baby in that position. My children are now 29, 27, 24, and 11.
You may find yourself wondering if your baby can sleep on his stomach, especially if he appears to be more comfortable that way. To prevent Sudden Infant Death Syndrome, or SIDS, which remains a threat until your baby is 12 months of age, it is best for her to sleep on her back, instead of her stomach.lthough it is safest to put your baby to sleep on his back, it is safe for him to spend some time on his stomach while he is awake. According to Healthy Children, you should give your baby time to play on his tummy two to three times a day.