to be honest..i once dated a woman that looked that skinny. the girl ate like a cow (and kept it down)...she was just super skinny. doc told her when she decided to have kids, it would be a challenge.
one of my great friends..again, emaciated waif-like body. she also ate a healthy diet. really really skinny. the poor girl had to go in for some jaw surgery. the doc made her eat ice cream daily for months before they would do it. she was all skin and bones. she now has 3 kids, and is still very thin. she is coming over for lunch sat, with her family. i am sneaking butter in her entire dish
some chicks are just like that...i think.