In how I Met Your Mother what episode do children appear in?

Children appear in many episodes of "How I Met Your Mother" but there's a specific episode where they play a significant role:

Season 3, Episode 16: "The Yips"

In this episode, Ted's kids (Penny and Luke) are featured in a flashback sequence where Ted is giving them a life lesson about how to overcome their "yips," a psychological block that affects athletes. This episode is important because it shows the kids' personalities and how they interact with their father, giving us a glimpse into Ted's future as a dad.

While they appear in other episodes, this one particularly focuses on Ted's relationship with his children and offers insight into his parenting style.