Vue Router default child route not loading initially

Here's what I've found to work:

...
  {
      props: true,
      path: '/sections/:id',
      name: 'route.sections',
      component: Sections,
      redirect: {
        name: 'route.details'
      },
      children: [
        {
          alias: '',
          path: 'details',
          name: 'route.details',
          component: Details
        },
        {
          path: 'secondary',
          name: 'route.secondary',
          component: Secondary
        }
      ]
    }
...

Adding in redirect: { name: 'route.details' } now makes the parent route redirect to the chosen child route.