# Query parent who just has only one child

**URL:** <https://discuss.elastic.co/t/query-parent-who-just-has-only-one-child/55716>\
**Category:** Elasticsearch\
**Created:** [July 18, 2016, 4:06am UTC](https://discuss.elastic.co/t/query-parent-who-just-has-only-one-child/55716 "2016-07-18T04:06:05Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Clay](https://avatars.discourse-cdn.com/v4/letter/c/65b543/32.png) [@Clay](https://discuss.elastic.co/u/Clay)\
**Post date:** [July 18, 2016, 4:06am UTC](https://discuss.elastic.co/t/query-parent-who-just-has-only-one-child/55716/1 "2016-07-18T04:06:05Z")

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I have some document and every doc have some other related documents.

Now, I want to know which parent doc has only one child doc.

What should I do ?

Or is there any better way ?

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<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\
**Post date:** [July 5, 2017, 10:34pm UTC](https://discuss.elastic.co/t/query-parent-who-just-has-only-one-child/55716/2 "2017-07-05T22:34:53Z")

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