In the answer, it said "That man has an older brother and an sister." (older was left out, making the sentence grammatically incorrect. Also, I answered "big sister/brother," this should be accepted. Thank you
형 is older brother in Korean. 누나 is older sister.
"and an older sister sseu"
sometimes i wonder where they get the random word suggestions from and where i would actually place that in the sentence~
-하고 means "and" and is used on nouns when making lists
Why is the counter for people not necessary in this sentence?
You typically don't need a counter when there is a singleton. That said, there are many ways to express a quantity of things with and without counters: