Complex sentence: They later split as a band, and two original members continued making music together but had to change their band name for legal reasons, their band is called 18 Summers, referring to the girl's age when she was killed.
Split into simpler sentences: They later split as a band, though two original members continued making music together, but had to change their band name for legal reasons. Their band is called 18 Summers, referring to the girl's age when she was killed.