Under the old covenant a woman who had given birth was required to offer a sacrifice. This sacrifice could also determine how well to do or not so well to do she was
“and he shall offer it before the Lord and make atonement for her. Then she shall be clean from the flow of her blood. This is the law for her who bears a child, either male or female. And if she cannot afford a lamb, then she shall take two turtledoves or two pigeons*, one for a burnt offering and the other for a sin offering. And the priest shall make atonement for her, and she shall be clean.”” Leviticus 12:7-8
We understand that Mary offered the birds rather than the lamb
“And when the time came for their purification according to the Law of Moses, they brought him up to Jerusalem to present him to the Lord (as it is written in the Law of the Lord, “Every male who first opens the womb shall be called holy to the Lord”) and to offer a sacrifice according to what is said in the Law of the Lord, “a pair of turtledoves, or two young pigeons.”” Luke 2:22-24
Later we see another Law of Moses being observed
“Three times in the year shall all your males appear before the Lord God.” Exodus 23:17
And males is my understanding meant males of age, not babies and children.
While the Bible doesn’t say the ages of Jesus’ half-siblings, it would not be unreasonable to assume that by age twelve had had one or more siblings but even if He didn’t, the journey to fulfill Feast of the Passover was costly, requiring only the males to partake. However...
“Now his parents went to Jerusalem every year at the Feast of the Passover.” Luke 2:41
Going from affording only birds to taking a woman and at least one child, every year, with all the costs associated with the travels, would this not indicate a step up in economic status?
Did they come into money to be able to afford traveling with the whole family?