Translation:I have three siblings altogether.
This doesn't sound like native English. We'd be more likely to put "altogether" at the beginning of the sentence or at the end. Or we'd use "in total" instead. Sticking it in the middle sounds strange.
It doesn't feel like natural English to put "altogether" in the middle of the sentence; it should be at the start or the end
Is "一共" strictly required here in Chinese? I notice they use it a lot in places where it's completely superfluous in the English translation.
the english sounds unnatural. agree with datsu23 and also "in total" should also be acceptable in place of "altogether"
It's particularly grating when the mouseover translations for "一共" include "in total" but this isn't allowed in the actual answers.
Is siblings always 兄弟姐妹 even if you have one little brother and a little sister or does it change to 兄弟妹?
It's a general term for siblings so you can use it regardless of which siblings you actually have.
where I come from only social workers and psychologists use 'siblings'. Normal people say 'brothers and sisters' it may take longer but it doesn't make your family sound like they're in some kind of social science study or report.
The English translation is unnatural. A natural-sounding sentence is "I have three brothers and sisters." No need to say "altogether," and "siblings" is technically accurate but not widely used verbally.
"I have three siblings in all" should not only be accepted, but is a more natural translation.
I think Chinese would more likely say, ”我們家有四个兄弟姐妹。" (They would include themselves in the total.)
Yes of the first only includes brothers, the second is brothers and sisters.