I fixed the mistakes you pointed out but let me finish the book before you try and call it bad lol, there's still lots if stuff that I have to make happen which is why you might be confused at first

They were lovers when they were human and now that they've crossed paths again they're picking up where they left off

He's only helping them to get Derek to stop killing his wolves.

Also even if his mom wasn't at home alot and she was working most of the time it's still his mother that's why he would be upset and care if she was murdered, wouldn't you?

The reason he went to the sheriff's office is because his mom died in that town so the sheriff would have had all the files from his mother's death, he was mad at his brother because he left and was gone for 100 years and in those 100 years his brother didn't even try to contact him, wouldn't you be mad in that situation too?

His brother is a normal vampire. I will explain how in an upcoming chapter.

Thanks for your advice, I'll keep this in mind.