Parent Visitor Visa with one dependent child to attend my convocation

[lewanjey]

I am inviting my parent and one younger sibling(under 18) to attend convocation.
So, Technically My father is Main applicant and my sister is dependent child.

So , Are both persons outcome dependent on one another or are independently assessed ?

I mean, Does it happen that my father gets accepted but My sister gets rejected?

Does my sister also need to prove home ties?

Note, I have my mother ,grandmother and brother also at home but not invited .