-- search for Trollgate on your phone, then install it. Now you need Kendra's login and password.
The login is easy; it's on the picture on the fridge at Kendra's house --
-- Kayak. There's no way to learn the password, though, so press the "Forgot password?" button. It asks for your mother's maiden name; that's Pierro, since she went back to her maiden name after the divorce.
The program then emails the password to Kendra. Now we just need a way to read Kendra's email. Remember the emails between Lia and Emil about monitoring Kendra's email? They mentioned using a specific computer program to do this.
The program you want is Parental Eye. Buy a copy from the clerk at the Abacus, then install it on Emil's office computer.
Now click on the Parental Eye icon to read Kendra's email and discover her password. (If Kendra has no email, go back into Trollgate and ask for that password.) The password is going to be the name of a famous composer -- Brahms, Mozart, Wagner, someone like that. Write it down, because it's random and I can't tell you which name you'll get.
Now you can log into Trollgate as Kendra and read her chat logs. In one of her conversations, she says something about construction in the basement behind a shelf.
So go back to Kendra's house, go downstairs (the stairs are to the left of the fridge), and click on the shelf to finally meet Lia.