Q: Did Mary and Joseph have other children besides Jesus?
A: Absolutely not.
Mary was subject to a specific provision of the the Mosaic Law, to wit:
Leviticus 27:28 Any thing that is devoted to the Lord, whether it be man, or beast, or field, shall not be sold: neither may it be redeemed. Whatsoever is once consecrated shall be holy of holies to the Lord. See also: Numbers 30:1-16.
Mary was and is a perpetual virgin, dedicated solely and completely to God from a very young age, her subsequent marriage not withstanding.
Once dedicated to God, such a vow survives marriage and everything else.
Joseph was her most chaste spouse, and a willing servant of God.