I am reading a book.

I have questions the last sentence.

(For your information, Rose is a normal kid and I am a physically challenged kid. They became friends after I joined the inclusion class) Rose tells me secrets sometimes. I know she bites her fingernails and she hates milk. She goes to church every Sunday but falls a sleep until it's over. Me too. She has a younger sister just like I do. She even likes country music. Sometimes she tells me about trips to the mall with her friends.

It would be so tight to be able to do that.

I was wondering what that in the last sentence refers to (trips to the mall?or talking about the trips to the mall?) or what the whole sentence means.

I really appreciate it if you answer this.