In my app.module.ts file  , I import (eagerly)  LoginModule which has its own routing module (login-routing.module.ts - let's say I can't change it) 
I also import  another routing module (AppRoutingModule - which deals with all lazy modules) .
app.module.ts:
    @NgModule({
                  bootstrap   : [AppComponent],
                  imports     : [
                      ...
                      LoginModule,
                      AppRoutingModule
                      ...
                  ]...
The login-routing.module.ts file has its own routing : 
login-routing.module.ts :
  const LoginRoutes: Routes = [
    {
        path     : 'welcome',
        component: WelcomeComponent
    },
    {
        path     : 'loginSms',
        component: LoginSmsComponent
    },
    {
        path     : 'loginPassword',
        component: LoginPasswordComponent
    },
    {
        path     : 'passwordExpired',
        component: PasswordExpiredComponent
    }
];
@NgModule({
            ...
          })
export class LoginRoutingModule
    {
    }
And AppRoutingModule has : 
const routes: Routes = [
    /* {    path      : "",    redirectTo: "/welcome",    pathMatch : "full"},*/
    {
        path    : 'app',
        children: [
            {
                path        : "home",
                loadChildren: "~/modules/home/home.module#HomeModule"
            },
            {
                path        : "payments",
                loadChildren: "~/modules/payments/payments.module#PaymentsModule"
            }
        ]
    }
 ...
Please notice that I've used ComponentLess route with prefix app just to organize routes.
So where is the problem?
I want to add the Login routes to "app routes" , so that I will access login routes as : 
app/login/...
In other words - now - AppRoutingModule should be : 
  path    : 'app',
            children: [
                {
                    path        : "home",
                    loadChildren: "~/modules/home/home.module#HomeModule"
                },
                {
                    path        : "payments",
                    loadChildren: "~/modules/payments/payments.module#PaymentsModule"
                },
                {
                    path        : "login",
                     //but how o I load all `login-routing.module.ts` routes here ?
                },
            ]
But LoginModule should be eager loaded and not lazy loaded , so I can't use loadChildern.
Question:
In short , how can I access the login module routes as :
app/login/loginPassword
instead of
/loginPassword
?