Just to clarify your question, it is not only “anti-Catholics” who think Mary had other children (daughters as well as sons, non? As per that one scene in the bible where his “brothers and sisters” were waiting for Jesus as he preached near Bethlehem?)…
Scholars who have studied the bible for decades upon decades and in all its manuscript forms and languages and translations who have no bias either way (ie, they are not “anti” Catholic) and some Christians and non-Christians, too, who have nothing against Catholicism, think it is indeed possible (and some think probable) that Mary had other children with her husband, Joseph.
As per above, lines in the gospels can be interpreted this way…but it doesn’t necessarily mean someone is “anti-Catholic” to think this.
Just wanted to put that out there.
Re: the “brother/sister” argument. All those experts mentioned know that everybody’s close family menber to a Jew was called brother and sister. That’s because there was no word for cousin.
For example
Because neither Hebrew nor Aramaic (the language spoken by Christ and his disciples) had a special word meaning “cousin,” speakers of those languages could use either the word for “brother” or a circumlocution, such as “the son of my uncle.” But circumlocutions are clumsy, so the Jews often used “brother.”
Since the NT was written by Jews who also wrote in Greek, and the OT was also written by Jews who wrote in Greek, (LXX Septuigint) all we have to do is see if adelphos/adelphoi was ever used in a broad Hebrew sense, not in the Greek sense, when they were writing in the Greek.
Example
Gen (LXX) Septuigint
13:8 εἶπεν δὲ Αβραμ τῷ Λωτ μὴ ἔστω μάχη ἀνὰ μέσον ἐμοῦ καὶ σοῦ καὶ ἀνὰ μέσον τῶν ποιμένων μου καὶ ἀνὰ μέσον τῶν ποιμένων σου ὅτι ἄνθρωποι
ἀδελφοὶ ἡμεῖς ἐσμεν
Lot and Abram were NOT brothers. Lot was the son of Haran, Abram’s brother. Lot was actually Abrams nephew. Abram was Lot’s uncle. Therefore, the Greek was used there with a broad Hebrew understanding of brother, which did NOT mean absolutely, children from the same womb.
When Abram referred to himself and Lot as brothers/adelphoi a wooden literal translation for brother is not possible.
Greek speaking Jews translated the OT from Hebrew to Greek, as well as the NT. The problem isn’t so much mistranslation as much as it is Jews thinking like Jews when writing in Greek. (people do this when thinking and writing in another language other than one’s native tongue)
For example Re: translations into Greek by Greek speaking Jews
Jews when translating the OT into Greek, knew the relationship of Abram and Lot. They could have used the proper word in Greek thereby correcting the loose Hebrew understanding of brother the Jews had. Lot was NOT brother of Abram. It was really nephew / uncle relationship. But the LXX didn’t correct that when written in Greek. The writers used alelphoi even though there were Greek words that could have been used to be more specific and correct the loose meaning Hebrew had. Therefore, adelphos/adelphoi didn’t have the wooden literal meaning for Jews people who read that passage, think it had. For Jews who wrote these accounts in Greek, brother was a loose term…
Another instance is that of Laban, who was an adelphos to Jacob, not as a brother, but as an uncle. In the New American translation, “kinsman” or “relative” is used in these Old Testament cases;
Another example
Rev 12:17
Mary is being discussed.
"Then the dragon was enraged at the woman and went off to make war against the rest of her offspring—those who obey God’s commandments and hold to the testimony of Jesus.(her offspring are considered all those who keep the commandments of God and give testemony to her son Jesus. ) Oy Vey that’s alot of kids
but it works only when speaking metaphorically.
We give latria=worship to God alone. Asking another to pray and aid us is not worship, it is petition, which we can ask of any other Christian, living or dead because all are alive in Christ, especially those in heaven with him.