ANOTHER excellent question! The Bible describes (often with misunderstanding) only 28 days of the life of Jesus here on earth.
The UB describes his life over his FULL life span, from babyhood, to childhood, to adolescent, with his earth family and friends, on to young adult and through his adult life until death, on to all of his resurrection appearances. Every description from a midwayer(like an angel) who witnessed it ALL!
Which would YOU like to learn? Depends on what a person wants...to know more of our elder brother and seek to follow him or to just know a few things and leave the living to the priests, pastors and clergy...