Ionic v4 tabs navigates to page instead of hosting it

Ionic Framework
1

I have created a tabs page in ionic v4 but every-time I navigate to the tabs page it goes straight to the default page. for example, if my tabs page is set up as below

<ion-tabs>

  <ion-tab-bar slot="bottom" color="primary">
    <ion-tab-button tab="tab1">
      <ion-icon name="home"></ion-icon>
      <ion-label>Home</ion-label>
    </ion-tab-button>

    <ion-tab-button tab="tab2">
      <ion-icon name="apps"></ion-icon>
      <ion-label>Feed</ion-label>
    </ion-tab-button>

    <ion-tab-button tab="tab3">
      <ion-icon name="settings"></ion-icon>
      <ion-label>Settings</ion-label>
    </ion-tab-button>
  </ion-tab-bar>

</ion-tabs>

and routing like

import { NgModule } from '@angular/core';
import { RouterModule, Routes } from '@angular/router';
import { TabsPage } from './tabs.page';

const routes: Routes = [
  {
    path: 'tabs',
    component: TabsPage,
    children:
      [
        {
          path: 'tab1',
          children:
            [
              {
                path: '',
                loadChildren: '../tab1/tab1.module#Tab1PageModule'
              }
            ]
        },
        {
          path: 'tab2',
          children:
            [
              {
                path: '',
                loadChildren: '../tab2/tab2.module#Tab2PageModule'
              }
            ]
        },
        {
          path: 'tab3',
          children:
            [
              {
                path: '',
                loadChildren: '../tab3/tab3.module#Tab3PageModule'
              }
            ]
        },
        {
          path: '',
          redirectTo: '/tabs/tab1',
          pathMatch: 'full'
        }
      ]
  },
  {
    path: '',
    redirectTo: '/tabs/tab1',
    pathMatch: 'full'
  }
];

@NgModule({
  imports:
    [
      RouterModule.forChild(routes)
    ],
  exports:
    [
      RouterModule
    ]
})
export class TabsPageRoutingModule {}

if I attempt to navigate to ‘/tabs/tab1’ the page tab1 is loaded and the tabs bar is not displayed

after further test the tabs only works when it is the default on app-routing.module

import { NgModule } from '@angular/core';
import { PreloadAllModules, RouterModule, Routes } from '@angular/router';

const routes: Routes = [
  {
    path: '',
    loadChildren: () => import('./tabs/tabs.module').then(m => m.TabsPageModule)
  }
];
@NgModule({
  imports: [
    RouterModule.forRoot(routes, { preloadingStrategy: PreloadAllModules })
  ],
  exports: [RouterModule]
})
export class AppRoutingModule {}

if at all you have other routes especially when empty path redirects to a different page, tabs doesn’t work as expected