Here is a nested expand to test this issue.
[expand title="Level 1" id="q1" rel="top-highlander" trigclass="must-be-one" expanded="true"]
[expandsub1 title="Nested Level a1" id="a1" rel="a-highlander"]answer a1[/expandsub1]
[expandsub1 title="Nested Level a2" id="a2" rel="a-highlander"]answer a2[/expandsub1]
[/expand]
[expand title="Level 2" id="q2" rel="top-highlander" trigclass="must-be-one"]
[expandsub1 title="Nested Level b1" id="b1" rel="b-highlander"]answer b1[/expandsub1]
[expandsub1 title="Nested Level b2" id="b2" rel="b-highlander"]answer b2[/expandsub1]
[/expand]
Level 1
Nested Level a1
answer a1
Nested Level a2
answer a2
Level 2
Nested Level b1
answer b1
Nested Level b2
answer b2
Here are some external triggers:
<a class="expandanchor" href="#q1">Level 1</a>
<a class="expandanchor" href="#a1">Level 1a</a>
<a class="expandanchor" href="#a2">Level 1b</a>
<a class="expandanchor" href="#q2">Level 2</a>
<a class="expandanchor" href="#b1">Level 2a</a>
<a class="expandanchor" href="#b2">Level 2b</a>