Using someone else’s car can be helpful, but it also takes a little extra time to get it set up for your needs! Unfortunately, the 2007 Chevy Malibu does not have Bluetooth—no models before 2009 come with Bluetooth as a standard feature.
However, your sister may have installed an aftermarket Bluetooth unit in her Malibu. If not, though, you won’t be able to use your hands-free calling or stream music. If having one installed is something your sister is interested in, Bluetooth-capable receivers are available for around $150.