either of two large organs lying within the chest cavity on either side of the heart; they supply the blood with oxygen inhaled from the outside air and dispose of waste carbon dioxide in the exhaled air, as a part of the process known as respiration.
Most babies first pull themselves up to a standing position between about eight months and 10 months. At this stage your baby will need to hang on to you or a solid piece of furniture. By 11 months she may be able to stand on her own.
Q: When will my baby start to walk? A: Most babies start taking their first steps between 11 and 15 months, but this milestone is hugely variable, and anywhere from 9 to 18 months is really considered normal.: Most babies start taking their first steps between 11 and 15 months, but this milestone is hugely variable, and anywhere from 9 to 18 months is really considered normal.