1. Height standards for two-and-a-half-year-old babies According to the standards of the World Health Organization, the average height of two-and-a-half-year-old boys is 87.6 cm, and the average height of girls is 86.4 cm. However, it should be noted that each child\’s growth and development is different, so this is only a rough reference value. 2. Factors affecting baby’s height 1. Genetic factors: The taller the parents are, the taller the child may be. 2. Nutrient intake: Adequate nutrition is very important for the growth and development of your baby. 3. Exercise exercise