I'm not sure I understand your question correctly, but it looks to me like you're animating the parent element vertically which throws off the calculations of those child element ScrollTriggers. Remember, ScrollTrigger pre-calculates exactly where things will hit the viewport at the correct spots so that performance is maximized (rather than constantly checking as you scroll to do a getBoundingClientRect() or something).   In general, it's a bad idea to animate the container vertically