Is this a malware problem?

This morning my girlfriend received an email saying that at 0310 this morning, someone logged into her Facebook acount via a certain IP address. The IP address is the one for her computer, it's the only computer in the house.

There was just myself and my girlfriend and i in the house, both fast asleep until about 9am this morning.

My girlfriend was logged inalready anyway on her Facebook all night, so even if one of us had gone on to her FB page, we wouldn't have had to log in.

Is this anything to worry about? Could it be someone else using her IP address?

Thanks for any help, i know little about how this all works.

Calv.

 

Yeah no other problems, i'll get her to sort her password out.

Thanks for your help, much appreciated.

Calv.