She gained weight after her first season I think, all of her spring 2008 shows she's bigger. I'm guessing that Teen Vogue was done around this time. Also, I think she gains weight on her upper body first, very noticeable on the arms. I think she then lost weight when she debuted lighter shade of hair colour. I think her weight loss has been gradual but it's more noticeable when she debuts her blonde hair. I also think we're definitely fooled into how tiny she is because her legs are significantly smaller than her upper body, even at her higher weight her legs are quite thin.