Like my 9 year old getting emotionally invested in an episode of Mickey Mouse Clubhouse.We always found this to be a huge benefit of the age gap.
My oldest (now a HS senior) has always enjoyed the "kiddie" stuff. She will freely admit that and let her excitement shine now, but when she was in that in-between age it was really nice for her to have the younger siblings as an "excuse" to enjoy things that she might have been embarrassed to admit around her peers. "But, mom, I really think the little ones would like to ride Peter Pan again... or Sister would really love to meet the princesses, maybe I should take her..."
I was an only child, but remember having a lot of fun "babysitting" littler kids with my mom because I could play Barbies.