Matthew 13

I find it interesting that as the Savior returned and preached in the synagogue in Nazareth that -

"...they were astonished, and said, Whence hath this man this wisdom, and these mighty works?

55 Is not this the carpenter’s son? is not his mother called Mary? and his brethren, James, and Joses, and Simon, and Judas?

56 And his sisters, are they not all with us?..."  (Matthew 13:54–56)

In mind would suggest two or more sisters.  Which would probably mean six or more siblings.