Little mouse

Bumped into a woman today with her little boy, she cooed over Logan and called him 'Maeuschen'...
Seriously? I can't think of a dog more unlike a little mouse, he clearly didn't stand on her foot...

Little miss bossy had her English corrections to do, what would you correct from this sentence?
'The woman has been on the computer for six hours'.

Apparently it should be, 'The woman has been working at the computer for six hours'.

At least they've started working on (or should that be 'in'?) Logan's playground now, only six months after the storm.