Hope to know Parent/Child template render order in Meteor - templates

Question

I have really issue on my app development, and hope to get your expert-level help.
<template name="inspection_go">
<div class="transitions-content">
<div class="row toolbar">
<div class="col s1">
{{#if previous_group}}
</i>
{{else}}
</i>
{{/if}}
</div>
<div class="col s4">
{{#if next_group}}
</i>
{{else}}
</i>Complete Inspection
{{/if}}
</div>
</div>
<div class="content">
{{> answer_draw_at_a_location group=current_group building=building inspection_id=inspection._id}}
</div>
</div>
</template>
<template name="answer_draw_at_a_location">
<div class="row" style="margin-top: 20px; height: 100%;">
<div>
{{#each questions_in_group}}
<div style="width: 100%;">{{> question_to_answer question_id}}</div>
{{/each}}
</div>
</div>
</template>
<template name="question_to_answer">
...
</template>
The above code shows parent - child template relation.
And this is the onRendered of parent/sub template.
Template.answer_draw_at_a_location.onRendered(function() {
console.log("parent");
});
Template.question_to_answer.onRendered(function() {
console.log("child");
});
The problem is below.
When I go to inspection_go page firstly, the answer_draw_at_a_location, that is, parent template's onRendered function invoked firstly, after then, the question_to_answer, that is, child template's onRendered function invoked.
And because when I click next_group or previous_group link, it recognize the same template, inspection_go in iron:router, it does not invoke the "answer_draw_at_a_location" onRendered function, so I changed to use #each to invoke it as below.
{{#each current_groups}}
{{> answer_draw_at_a_location group=this building=../building inspection_id=../inspection._id}}
{{/each}}
But now when I click prevoius_group or next_group tag, it execute onRendered function of child template ( question_to_answer ) firstly and after then execute onRendered function of parent template ( answer_draw_at_a_location ).
So I hope to know why it happens, and at least, is there a way to execute parent template onRendered function firstly and after then execute child template onRendered or vice versa.
Please help me.