What developmental milestone at 9 months indicates a baby is becoming more mobile?

At 9 months, the developmental milestone indicating increased mobility is crawling or cruising. This period is crucial for a baby’s mobility development as they begin to explore their environment more fully. Crawling allows them to move around independently, enhancing their ability to reach for toys and engage with others. Cruising, which involves pulling up to a standing position and moving along furniture, further demonstrates their growing strength and coordination.

While standing alone and walking independently are significant milestones as well, they typically occur later than 9 months. Rolling over, while an important skill that develops earlier, does not necessarily indicate that a baby is becoming more mobile in the same way that crawling and cruising do. Essentially, crawling or cruising at this age marks a pivotal leap in a baby’s physical development, leading to more active exploration of their surroundings.