I think Christine has to be taller than 5'7. In pictures where Stevie has her 5 inch heels on, she's still shorter than Chris, who's wearing flats. I'm 5'7 1/2" and I've had short people with heels on standing next to me and they're almost the same height.
Poor John - he fades into the background so much that no one notices his height! I'm beginning to love that guy, just standing in the shadows doing his thing and not getting wrapped up in the limelight. He's kinda cute.
Here's the pic I was thinking of:
