Y por que lo de la cama......

Y por que lo de la cama......
 

if someone says "y por que lo de la cama" what are they saying?

i had asked her what time she goes to bed and wakes up and she told me and then she asked me this question.

it looks like a funny way of asking why are you interested/asking about the bed.

The article "lo" followed by a "de" phrase is used in the sense of "the matter concerning" or more colloquially "the business about", "the situation of".

I assume she was using "por qué" so I would read it as "and why (are you asking about) this business/matter/situation of the bed?"

I also agree... "¿Y por qué lo de la cama?" is asking What about it?/Why should it be important/interesting?/Why do you ask?