The mystery of mother's feet

[Ringading]

I refer to this one.

Given the amount of obscured space between "rub," mother's," and "feet," one is led to wonder: does she get particularly descriptive about her feet and the rubbing process, is there a long list of things she wants to have rubbed in a very specific way, or are the rubbing; possessive; and feet completely unrelated? Inquiring minds want to know!