Is it strange that my 9 year old sister doesn’t know how to tie her shoes?

I recently moved back home so I’ve been helping her get ready for school on Fridays. Today is the first day that she hasn’t worn crocs or pull on boots so I guess I never really thought about it. She said that “mom hasn’t taught her yet”. I could’ve swore that our mom taught me how to tie shoes when I was a lot younger. Do you remember what age you were when you learned? If you have kids how old were they?

Laceless shoes are more common now so I guess I could see how it wouldn’t be as important to learn young. My mom is also someone who made me figure out a lot of things by myself when I was younger so I’m honestly not surprised about this.