Makes some sense.

Rose: I drink that's all
Bellatrix: so that's why there's wine, tea, and Sprite in the fridge and... Milkshake?
Rose: glow having a baby so milkshake is best choice for a growing baby flower

hM. Ok. Then about the food thing...?

Rose: uhm there is blood pulsing in my bones except my joints Soo I am living
Bellatrix: that explains alot

I mean she is a skeleton so she's technically not living but y'know.