Well, the age of parents in a Christmas story could be all over the place. There are traditional Christmas stories where the parents seem to be mature adults, perhaps around 35 - 50 years old. However, in some modern interpretations, the ages can be more flexible. If it's a story about a young family starting out, the parents could be in their late twenties. But really, it depends on how the author wants to portray the family dynamics in relation to the Christmas theme.
The Bible doesn't specifically mention the age of Mary and Joseph when Jesus was born in the Christmas story. We can only assume they were likely in their young adulthood as was common for people to marry and start families at a relatively young age in that era.
We can look at the number of children they have. If they have a lot of kids, they might be a bit older, maybe in their forties. Also, their occupation can give a clue. If they have a well - established career, they are likely to be older, say mid - thirties or more.
One way to estimate the age of Mary might be by looking at the cultural norms of the time. In that era, it was not uncommon for girls to be married off relatively young. So Mary could have been in her early to mid - teens. As for Joseph, since he was a carpenter, he was probably a bit older, maybe in his twenties, as he would have had some time to learn and establish his trade.
In the Christmas story, the significant parents are Mary and Joseph. Mary was a virgin who miraculously became pregnant with Jesus through the Holy Spirit. Joseph was a just man. He was betrothed to Mary and became Jesus' father in a worldly sense, taking on the role of protecting and providing for the family.