Angular 2에서는 형제 구성 요소가 어떻게 통신할 수 있나요?

// shared.service.ts
@Injectable()
export class SharedService {
  dataArray: string[] = [];

  insertData(data: string) {
    this.dataArray.unshift(data);
  }
}

// parent.component.ts
@Component({
  providers: [SharedService],
  directives: [ChildComponent, ChildSiblingComponent]
})
export class parentComponent { }

// child.component.ts
constructor(private _sharedService: SharedService) { }
ngOnInit(): void {
  this.data = this._sharedService.dataArray;
}

// child-sibling.component.ts
constructor(private _sharedService: SharedService) {}
addData() {
  this._sharedService.insertData(this.data);
  this.data = '';
}