Angular UI State Change (ionic)

I have the following states defined in my project.

A.substate1
A.substate2
A.substate3

B.substate4
B.substate5
B.substate6
I have a launch screen, which has a state named ‘launch’. From there I go on two paths A and B. Depending on what I click I go to that state and hence the sub states.

Please note that ‘A’ and ‘B’ are abstract states.

Now, as you can see that there is no connection between the states A and B.

So, the issue is that when I am directly changing state from, lets say A.substate2 to B.substate1 , I get an error as “Cannot read property ‘run’ of null”

But if I change states from A.substate1 to A.substate2, then I don’t get any such error.

So, I wanted to ask if I am making any fundamental mistake that I should have a parent state which has to be common to all the state. Something like: Home.A and Home.B, so then my state-tree will look like this:-

Home.A.substate1
Home.A.substate2
Home.A.substate3

Home.B.substate4
Home.B.substate5
Home.B.substate6
So, now Home is the parent state.

Please guide me if the first scenario I am using is a valid one, or this is not the way things are done. I am using ionic framework and Angular-UI/ Angular-JS for my routing engine.