Was Mary perpetually a virgin?

My son keeps battling me about the Roman Catholic Faith.
I love the Catholic Church deeply but I am still learning so much.
Can you please help me answer him.?:confused:
This is what he asked:

“Was reading Matthew 13:55,56 and thought of you Mom:)…‘Is this not the carpenters son? Is not his mother called Mary? And his BRETHEREN James, and Joses, and Simon and Judas?56 And his SISTERS, are they not all with us? Whence then hath this man all these things?’ if Mary is forever virgin by the doctrine of the immaculate heart of Mary by the Catholic teaching in Canon law and the Catholic Catechism…why is it that Gods Word says that Jesus had younger brothers and sisters…Mary apparently had kids after the virgin birth of Jesus…according the the bible…are we gonna believe the bible or the canon law of the catholic church…these are clearly different teachings…”

Thank you.

The following links should assist you in better understanding Mary’s perpetual virginity. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.
Recommended Reading:

*]Doesn’t Scripture imply that Mary had children other than Jesus?
*] Did Jesus have brothers?
*] Perpetual Virginity: Why is this important?
*] Mary: Ever Virgin
*]How do we know Mary was a perpetual virgin?
*] Why should any doctrine not explicitly referred to in the Bible, be listened to?
*] How do you respond to “Everything you need to know is in the Bible”?
*] How can we know a doctrine is true if it’s not in the Bible?
*] How do we know that the Protoevangelium of James is credible?
*] Does Church Tradition exist only to interpret Scripture?
*] Non-Canonical Writings…
*] Oral Traditions not found in the Bible
*]Immaculate Conception and Assumption

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