I wonder if she's doing it deliberately, to annoy me?

I was out with the family for dinner at some friends, and when we got home, my sis said she needed on the 'puter to do some work for uni. Fine, I'll just do some studying. No distractions in the kitchen, I thought, so I took some past papers and started work, with the radio on in the background.

After twenty minutes or so, sis arrives, and dumps a whole load of stuff on the table. Printouts, card, a toolbox, some cutting boards.

"I'm going to need to use this table, can't you go elsewhere?"
"Um, no, I'm working here"
"Fine, I'm telling mum"

She returns shortly after, and starts clattering around in some drawers

"Could you at least keep the noise down," I said as she turns off the music..

So, I get to the stage in my revision where I stop taking things in.. and decided to go and veg in front of the computer for a while. As I start to pack my stuff up...
"I'll be needing on the computer again soon"
(and, of course, since she's doing work for a final project which must be in tomorrow, I have no choice...