They also start to walk backwards and in circles and begin to run. They can also not only walk up the stairs with their hands and feet but are now able to hold onto the handrail and walk up. Near the end of their second year, complex gross motor skills begin to develop including
The development of these abilities involves a progression from basic movements (walking backwards, in circles) to more complex ones (running, stair climbing with handrails).  This is consistent with the growth of gross motor skills over time.