This is my theory of 3 girls being buried "that night."
NOTE: Again, this is my own personal theory that doesn't make this true kwa any means but I think this is my only theory that I have so far, that could end up being true..

1. Sara Harvey went missing around the same time Alison did.
(We find this out when Emily and Hanna go to visit Sara's Marafiki Claire and Tina)

2. Remember when Sara was found in the dollhouse? (Yes the same one where the liars were) The cop asks her name she alisema "I'm Sara, Sara Harvey" This mirrors when Mona thought she was Alison she alisema "I'm Alison, Alison DiLaurentis" seems to be a common thing in Rosewood people lying about their identity.

3. The Sara Harvey on the website looks NOTHING like the Sara Harvey we know.

4. Sara and Alison were almost exactly alike from the blonde hair, to the blue eyes, the way they walked, and lets not forget, Sara Harvey was also her schools "it girl" she brought her group together just like Alison, and both girls were the reasons why their Marafiki even became friends, so it's possible someone mistook the girls and could have possibly hit Sara instead of Alison.

5. (This one is a side note) wewe notice when Hanna and Emily went to visit with Claire and Tina, Claire resembled both Alison and Hanna where Tina resembled Emily?

6. Avery also saw Sara last (just like Spencer saw Alison last) it's almost like the groups mirror one another, why if they weren't somehow connected to each other?

7. Back to Sara's friends. Don't wewe think if their friend was found they would be happy and come to visit her? Unless it wasn't really her.

8. Let's talk about that yellow tank top. Alison, Mona, Bethany, Sara, and possible charlotte have all worn it.
(Alison the night she disappeared, Bethany the same night (keep in mind she snuck out of Radley) Mona when she was forced to pretend to be Alison, and Sara when she was found in the dollhouse with the others. I don't believe we SAW charlotte wearing one (or am I wrong?)

What do wewe guys think? Could 3 girls have been buried that night? Is it the REAL Sara Harvey?