Final answer:
Most babies, about 90 percent, have the ability to stack two blocks by 15 months old. This milestone is part of their fine motor development and typically developed between 12 to 18 months.
Step-by-step explanation:
According to developmental milestones recognized by pediatricians, about 90 percent of all babies will be able to stack two blocks by the age of 15 months. This task is a part of a baby's fine motor development and involves the use of their hands, fingers, and eyes working together. Each baby's development can vary; however, most babies will start to develop this skill between 12 to 18 months
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