Relationship in household (including grandchildren) (RLGP)

Latest release
Census of Population and Housing: Census dictionary
Reference period


This variable describes the relationship of each person in a family to the family reference person. Where a person is not part of a family their relationship to the reference person is described.

This variable is different from the Relationship in household (RLHP) variable, as it:

  • has an extra grandchild type, being ‘Dependent student grandchild’
  • classifies lone grandparents (with no parent-child relationship present in the household) as ‘Lone parent’

This variable can only be used with other related grandparent/grandchild variables. These variables are:

  • Child type (including grandchildren) (CTGP)
  • Grandparent families (FMGF)

It cannot be used with standard family variables.


Persons present in an occupied private dwelling on Census Night


Husband, Wife or Partner
10Husband, wife or partner, opposite-sex couple
15Husband, wife or partner, same-sex couple
Lone parent 
21Lone parent
Child under 15
31Natural or adopted child under 15
32Step child under 15
33Foster child under 15
34Grandchild under 15
35Otherwise related child under 15
36Unrelated child under 15
Dependent student
41Natural or adopted dependent student
42Dependent student step child
43Dependent student foster child
44Dependent student grandchild
Non-dependent child
51Non-dependent natural, or adopted child
52Non-dependent step child
53Non-dependent foster child
54Non-dependent grandchild
Other related individual
69Other related individual (nec)
Non-family member
71Unrelated individual living in family household
72Group household member
73Lone person
91Visitor from within Australia
99Other non-classifiable relationship
Not applicable 
@@Not applicable
VVOverseas visitor

Number of categories: 31

Not applicable (@) category comprises:

  • Persons in non-private dwellings
  • Persons in migratory, off-shore or shipping SA1s

See Understanding supplementary codes for more information.

Question(s) from the Census form

What is the person's relationship to Person 1/Person 2?

What is the person's date of birth and age?

Is the person: Male; Female; Non-binary sex

Is the person attending a school or any other education institution?

How this variable is created

This variable is created using responses to the relationship in household, sex, age and attendance at an educational institution on the Census form.

Sex (SEXP) is used to determine whether the person is in a same-sex or opposite-sex couple.

Age (AGEP) and Student status (STUP) information is used to determine what type of child the person is:

  • child under 15 (including grandchild under 15)
  • dependent student (including dependent student grandchild)
  • non-dependent child (including non-dependent grandchild)

This variable is similar to Relationship in household (RLHP), but there are three key differences in how Relationship in household (including grandchildren) (RLGP) is processed. The table below outlines these scenarios and how each variable classifies the person.

ScenarioHow it would be coded in RLGPHow it would be coded in RLHP
Person is a dependent student (15-24 years) and has a relationship of grandchild to Person 1/Person 244 Dependent student grandchild63 Non-dependent grandchild
Person is aged over 24 years and has a relationship of grandchild to Person 1/Person 254 Non-dependent grandchild63 Non-dependent grandchild
Person is a lone grandparent (no parent-child relationship present in the household)21 Lone parent64 Grandfather/grandmother

Persons temporarily absent on Census Night are also taken into consideration when deriving this variable. This helps with the identification of some families and for distinguishing between lone person and group households.

During data processing, families are identified and created based around a ‘family reference person’. For cases where a child or non-family member was listed as Person 1, a more appropriate person is selected to be the reference person.

History and changes

This variable was first included in 2011.

No changes have been made for 2021.

Data use considerations

Family coding processes

During Census family coding, all children under 15 years of age are allocated a nominal parent if their parent/s are not present in the household on Census Night, or if the parent/s were not reported as temporarily absent. Nominal parents can be the child's sibling, grandparent, aunt/uncle or other related individuals.

Grandparent families are recognised where a grandparent/s is allocated as the nominal parent or where there is only a grandparent-grandchild relationship present in the family and no parent child relationship. When a parent is temporarily absent from the family and their relationship to the child cannot be determined, the relationship cannot be coded. This can result in a small number of children being reported incorrectly as grandchildren when a parent is simply absent on Census Night.

RLGP may not represent caring responsibilities

Users should note that grandparent-grandchild relationships are constructed for the purposes of family coding in order to create a statistical family. It may not be representative of who provides care.

For example, a scenario could be that a 20 year old grandchild lives with her grandmother. She is a full-time student and is dependent on her grandmother. Alternatively, she may have moved in with her grandmother specifically to take care of her. It is important that users do not make assumptions about grandparent families.

This variable does not have a non-response rate as it is created during Census processing by using responses from more than one question on the Census form.

Related variables and glossary terms

  • Child type (including grandchildren) (CTGP)
  • Grandparent families (FMGF)
  • Relationship in Household (RLHP)
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