3-month-old weight and length. By 3 months old, your baby has probably grown significantly since birth. In fact, some babies will have doubled their birth weight! (The general rule of thumb, though, is that babies double their birth weight by 4 months and triple their birth weight by 1 year.) More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.