Hi, I'm dating a 18 yr old girl who lives in her grandpas house but lives alone. She lives on a family business. She was driving a business owned car and left windows cracked outside her house. It rained and her cousin (a part owner of business) seen it. So he bangs on the door while she's upstairs in bathroom. While she's upstairs he gets a way into the basement through a garage passage and tries getting in the inner door of the house by smashing it with his fist. HE then fails but dents the plywood door up and goes over to the shop to get a crowbar. I got a call someone was breaking into her house so I drive over and he's seen carrying a crowbar to try break in. Then there's a confrontation non physical and we all depart. Now tell me this. Just because the house is on a business and the grandpa owns it. Can it be justified that its all right for a cousin to break into his cousins house where this 18 year girl has been living alone? She's been terrified and has had serious stress from this for months. Not to mention this cousin that tried breaking in has tampered with 1 piece of her mail by opening it. It went to wrong building on business. What can be done if anything? Does owning parts of your business justify wrong doing?

The reasoning for trying to break in was to make sure she was OK because she wasn't answering the door. Sounds like a perfect reason to be above the law right?

What would be the desired outcome of the suit if one was indeed brought?

Her grandfather would have to sue for damages to the property.
I don't think she has a lawsuit for emotional distress, especially in that there was no physical violence, and there's really no evidence, nor do I suspect she has been to therapy.
(And certainly 'we' as you ask in your title don't have a lawsuit together.)

She has every right to get a restraining order (RO) from her police station, regardless of where she is at any given moment or who owns the place she is at that time. It's an order to stay X feet away for X amount of time. That's what it's called in the US.

Sounds like he was trying to be helpful by trying to close her windows. I see no lawsuit.