average length of a 15 month old girl
Physical Development. Growth has begun to slow down in this second year, gaining around 3 to 5 pounds and 4 to 5 inches in height. On average, a 15-month-old female weighs 23 pounds and measures 30 1/2 inches, notes the American Academy of Pediatric's website, HealthyChildren.org.Boys this same age weigh 24 1/2 pounds and measure 31 inches in length, on average.hysical Development. Growth has begun to slow down in this second year, gaining around 3 to 5 pounds and 4 to 5 inches in height. On average, a 15-month-old female weighs 23 pounds and measures 30 1/2 inches, notes the American Academy of Pediatric's website, HealthyChildren.org.