Elixir is the one in the hoodie, Mackenzie is the one with bright blue eyes, and Jack is the blonde.
Mackenzie and Elixir are twins, but Mackenzie is older. Mackenzie is a gentle, sweet, outgoing person while Elixir is a very selective talker, quiet, and somewhat of a loner.

Jack is the guy that got in between the twins, since they both like him, but he likes mackenzie.
Elixir is fed up because everyone loves Mackenzie including people she's close to. She's always being told to speak up, be nicer, be more like Mackenzie and she hates it. She ends up running away, and goes to an orphanage. She is adopted by Cecelia eventually, and ends up telling her everything.