i seem to be getting email for someone else in my account

my gmail address is blah.blah@...

it seems some young girl has signed up for my same address without the dot. blahblah@ every so often i get email for her. like when she forgot her password for some social networking site and tried several times to change it, or when her friend want to send her slightly derogatory email, or when her social networking sites want her to update stuff. it's not fun. is there a way to make sure her email goes to her account only?
 
sad I’m annoyed.
Inappropriate?
3 people have this problem
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