How to access child controller data from parent view in AngularJS

I have an ionic view like this -

<ion-nav-bar class="header-panel" align-title="center">
    <h1 class="title offer-title">Title 1</h1>
</ion-nav-bar>

<ion-tabs class="tabs-royal">
    <ion-tab title="Tab 1" href="#/somelink1">
        <ion-nav-view name="someview1"></ion-nav-view>
    </ion-tab>
    <ion-tab title="Tab 2" href="#/somelink2">
        <ion-nav-view name="someview2"></ion-nav-view>
    </ion-tab>
</ion-tabs>

The someview1 and someview2 are bound to their respective controllers, but they can represent data dynamically, say with Id=1 or Id=2 or Id=3 and so on.

How can I access this Id information which the tabs hold in the parent level so I can change nav bar title dynamically like Title 1 or Title 2 or Title 3 respectively.

Essentially what I am asking is can we have a top level controller which holds information what child level controller data is?

Note: The routes are set-up using ui-router.

Thanks in advance.