Why Was Everybody Calling 'Megan' ( Lucy Hale) 'Honey,' etc?

Each instance was towards the end of the movie. When they all run back to the cabin after finding Kyle's body, Tyler is shouting for Megan & says "Megan, baby?" Next is when "Jenna" (Haylie Duff) & Mark go upstairs, Jenna calls her "honey."

Now, I know that "Megan" was a bit younger than all of them, but certainly not young enough to be addressed as though she were a child.