Is a circular link between business objects (in a hierarchy) shared?

Question

The Linq-to-Sql classes provide parents with a link to a child collection, as well as a child link to a parent (single or collection). This allows you to "drill" in both directions , and it seems quite convenient.

Is it a design that is also suitable for using manually created business objects (POCOs or others)? When; What were the pros / cons or specific situations when this would be recommended?

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EDIT1:

I think mainly about logical behavior; which means not user interaction, but like programs related to financial transactions, gaming software, etc. What to do if you are dealing with a child object and then need some parameter of its parent. This seems pretty convenient, but maybe these are other parts of my encoding methods that are a problem and make me feel like I need it.

Answer 1

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Answer 2

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{
  Person ContactPerson {get;set;}
}

class Person 
{
  Company Company {get;set;}
}

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Answer 4

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