"Who is your older sibling?"
Translation:Siapa kakak kamu?
i found this...."adalah" & "ialah" (copulas, linking verbs) are used in non verbal clauses, and the use is optional. "ialah" can only be used for 3rd person subjects.
The subject and the predicate are usually nouns/noun phrases (see KBBI examples). 'adalah' is placed between the subject and predicate. The word order is as follows : [subject] + "adalah" + [predicate]