Leaving Time question

In the end she left with the Detective that helped her. And serenity explained how kids could see ghost and other ppl too so i believe thats why her father could as well. His mental state let him see her.

Many ppl do believe ppl w mentl illness vould see things others cant.

She left with Virgil the detective in the end of the book.

But it doesn't add up because Thomas said he saw Jenna taking all of the vegetables she didn't like out of the fridge that day and giving them to the animals and how he was so excited at what she could do at the age of 3 that he couldn't bear to think about what she would be able to do at the age of 23...then he didn't just see her he is stuck in the past right?

I believe within the rules of this book, those who see ghosts interact with them as real people, so they can touch them.

There are still other parts that don't add up:

1. Jenna is able to get the waitress at the diner, but Virgil cannot. Neither of them should have been able to do that.
2. Tallulah cannot be touched when Virgil starts freaking out about the tooth. This maybe is because it represents Virgil realizing he's dead.
3. Ghosts age?

Yes. Somewhere it mentioned that people who were mentally ill were more open to the spirit realm or something like that. Personally, I don't like these blanket "rules" about the mentally ill in literature, but that's how the universe works within this novel.