I think "Do you have siblings?" would be a correct alternative. Reported on Nov. 19, 2017.
I just reported this too in mid December! Mine was marked wrong for, "Do you have siblings?" Beta is giving me a headache.
I have also reported this 01/05/2018. I hope they add it as an option soon.
Do you have any brothers or sisters.
Yes both with and without "any" should be accepted. "Sibling" is fairly technical in English and not used in daily conversation that much.
Ha where's 哥?
"Do you have siblings" should be correct.
兄弟...妹 : all if this is siblings ?
What would singular sibling be ?
A proper way should be: Do you have siblings?