When do infants typically climb on hands and knees and feet up stairs?

Infants typically develop the ability to climb on hands and knees and feet up stairs around 10 to 11 months of age. This developmental milestone is part of their gross motor skills progression. At this stage, babies become more coordinated and stronger, allowing them to pull themselves up and navigate surfaces more effectively.

Around 10 to 11 months, many infants start to demonstrate more purposeful movements and exhibit an increased ability to explore their environment. This includes not just crawling but also beginning to pull up to stand and walk, which contributes to their climbing skills. They often practice these skills in safe environments, which helps build their confidence and physical strength.

At earlier ages, like 6-7 months or even 8-9 months, infants are still consolidating fundamental movements such as rolling over and beginning to crawl but are usually not yet adept at climbing stairs safely. By the time they reach 12-15 months, they are usually more confident and skilled in their movement abilities, possibly leading to a transition to walking without assistance and exploring more challenging climbing situations.