Oh god, so many things wrong with this. First off, guy on the left: faces don't work like that. It looks like his eye sockets are protruding out of his head. Which they don't. That's why they're sockets.
The kid in the middle left... well, there's not much wrong with him, but the shading is weird. Something is just off.
And the girl on the middle right? Is that like... a Megan Fox lookalike whose face is too big for her head? Especially with the whole... hair line thing. It's scary.
And finally, poor Olive. She looks okay, just really serious. Plus here hand. HER HAND. It's like her fingers got squished.