That was then this is now - S.E. Hinton

Since childhood, Baron and Mark have been as close as brothers. Now things are changing. Bryon’s growing up, spending a lot of times with girls, and thinking seriously about who he wants to be. Mark still just lives for the thrill of the moment. The two are growing apart – but holding on – until Bryon makes a shocking discovery about mark. Then baron faces a terrible decision – one that will change both their lives forever.