Not only that - DL claims it's a question, but the audio doesn't sound like one.
In English the sentence is not a question without the "Do..."
So yes it's necessary.
I don't think that it is; however, when translating this to English, it just sounds more natural.
It can be a general question asking if you have siblings (brothers and sisters).
Excuse me, but aren't 'siblings' the same as 'brothers and/or sisters'? Website rejects these options....
If the plural object is not a person, do we need to use delli/e after the verb avere? Hai delle forchette?