Why does Baby Jesus Look like an Old Man in Medieval Religious Iconography?

When perusing the Medieval religious iconography in a museum, it is difficult to miss baby Jesus with the face of a grown man! Why was this his popular depiction?

Why does Baby Jesus Look like an Old Man in Medieval Religious

History of art's ugliest paintings of Jesus - Artsper Magazine

Baby Jesus in art and the long tradition of depicting Christ as a

Medieval Pilgrimage to the Relics of the Nativity

Iconography – American Association of Iconographers

On The Origin of Ὁ ὬΝ in The Halo of Christ – Orthodox Arts Journal

The life of Christ in medieval and Renaissance art

Saint Joseph As Baby Daddy in Nativity

Painting the Life of Christ in Medieval and Renaissance Italy

Nativity, Definition, History, Themes, & Facts

The Roman god Bacchus as a Christian icon