Angular – route to first available child route

This is my current router config. My desired behaviour is to redirect to the first available child route. So for example, if child1 cannot be accessed due to the route guard, it should attempt to load child2. Originally, I had this code that just redirected to child1, but this fails if child1 is not accessible.

const routes: Routes = [
  {
    path: '',
    redirectTo: 'child1',
    pathMatch: 'full',
  },
  {
    path: '',
    component: ParentComponent,
    children: [
      {
        path: 'child1',
        component: Child1Component,
        canActivate: [routeGuard],
      },
      {
        path: 'child2',
        component: Child2Component,
        canActivate: [routeGuard],
      },
      {
        path: 'child3',
        component: Child3Component,
        canActivate: [routeGuard],
      },
    ],
  },
];