Leukocytes are not limited to blood. They occur elsewhere in the body as well, most notably in the spleen, liver, and lymph glands. Most are produced in our bone marrow from the same kind of stem cells that produce red blood cells. Others are produced in the thymus gland, which is at the base of the neck.
Once your baby is past 3 months than that is no longer a newborn. But that isn't considered a toddler either yet. They are a baby up until they start to walk then they are called a toddler. Source(s): My opinion. chicken2008 Â· 6 years ago. Thumbs up. 0. Thumbs down. 0. Comment.
A human baby in his first year of life is referred to as an infant. However, until they complete first three months of their lives, small babies are newborns and technically they are infants between 3-12 months of age. However, there are places where human babies up to 3 years of age are referred to as infants.