FLR (M) dependent children

Hi

there is a section in the application whereby I am required to add details of any dependent children including the ones not applying with me.

I have a 1 year old from my sponsor who is British and thus not subject to immigration control, I understand I should add his details.

my sponsor has a son who is 5 years old from his ex girlfriend he doesnt live with us, do i have to enter his details as well? I have to provide his address and passport number and whether he has lived anywhere else ..... I find these details not relevant to my application do I still have to add his details in that section? or should i just add my own child info?

Thanks in advance for your assistance.