Time apart

hello everyone well ok my older brother is the lead singer in a band that recently is getting famous and famous there known as hinder I dunno if you all know who that is but anyways,his girlfriend I think is cheeting on him she jsut acts funny never calls he calls her and stuff so if anyone could gimme some signs to lok for around her that would be great thanks

If things seem different from the beginning of their relationship to now that could be a sign somethings up. If she isnt calling him like she used to. If she seems to be more distant. Not spending as much time together. Seems to be spending more time with her friends. Maybe standing him up if they have plans to be together. Arguing with him more. Not being in the best of moods around him. If he suspects shes lying about certain things. Those basically are some indictions for something going on with her, not necessarily cheating.
Dont jump to conclusions though unless you have solid proof of her cheating. Ask people, or maybe follow her on a night she isnt with your brother!