Visitor Visa: Is Statutory Declaration of Common Law Union required to fill?

[shawnwashere]

My grandparents, and my brother and his wife are applying for temporary visitor visa. Do any of them need to fill Statutory Declaration of Common Law Union? Is saids if applicable on cic website but I can't find information on if any of them need to fill it.
Thank you.

 

[Qwertypod]

They are all married I assume, so no.

 

[shawnwashere]

They are all married I assume, so no.

Yes they are. Thank you.