Context tells us that the neighbors were astonished at the performance of a kid who's brothers and sisters from the same family didn't turn out the way he did (wonder why.. LOL).You're right. There is a scriptural account of JESUS' neighbors referring to His mother, father, sisters and brothers.
But, you're wrong about what the context says.
JESUS' neighbors were put off by His daring to teach them.
Why, they said, Isn't this Jesus, the son of that carpenter Joseph ? Well, he grew up in my neighborhood. He played with my kids. I went to the market with his mother, Mary. Aren't James, Joseph, Jude, and Simon his brothers ? Aren't his sisters still here in town with us ? Well, just where does he get off thinking he's got something to teach us ?
All of the gospel accounts say that they (His townsfolk) were offended at Him. That's what the text says.
Perhaps you'd best take another look at it.
But, no matter. Either way, there is no denying that JESUS' neighbors were sure that JESUS had (4) brothers and sisters.
I'll be nice and not say what effect this has on your conclusions.