Did Christ have siblings?

Do Christ had a sibling? Many people wonder not only about marital status Christ during his earthly life, but also over whether Christ had siblings. It's hard to really come up with this kind of information at Mass, or even by looking through the Scriptures, because it's never the main gist of Christ's teachings. But it is worthwhile sometimes to focus on these kinds of facts as well. The New Testament hides nothing from us and informs us not only about the Holy Family, but also about the brothers and sisters of Christ.

The Gospels of Mark and Matthew enumerate for us 4 brothers of Christ, linking them also to Mary and Joseph. Christ was thus supposed to be Jacob's brother, Joseph, Jude and Simon. His (at least two) sisters are also mentioned there. However, the interpretation of these words, which somehow conflict with Mary's perpetual virginity and Joseph's legacy, is not clear. According to these accounts Jesus He should have been their only son after all. So it could really be about cousins of Christ, and as we read in the Gospels that their mother was Mary, the mother of Joseph and James, present at the Cross, the sister of his mother Mary Cleophas. So most likely the said Mary Cleophas, had to be a cousin or sister-in-law of Mary, the Mother of Christ. Thus Christ's siblings is probably only reduced to the existence of His cousins and cousins, from His Mother's sister.