Player Push Player up a ladder until reach the top even if W is not click

When i was going down a ladder and my sister when up it, when we collide i begin to head up with her and I told her to stop but we still keep going up until we ended up where I begin which was the top of the ladder. I know this in 15w50b when I was play with my brother when we were both headed down the ladder to get to the end portal.