Baby photos vs older child photos: why resemblance changes with age

Families often notice that a baby seems to resemble one parent, then appears to resemble the other parent several years later. Facial growth helps explain why both human impressions and AI similarity scores can change.

Babies do not have adult facial proportions

Early in life, the forehead, cheeks, jaw and other facial regions have proportions that differ from those seen later. As the child grows, those relationships change, which can make inherited traits appear more or less prominent.

The lower face develops

Growth of the jaw and changes around the mouth and nose can alter the overall shape of the face. A resemblance that was dominated by the eye area in a baby photo may be balanced by other features later.

Expressions also mature

Older children develop a wider range of familiar expressions. Family members may recognize a parent's smile or eye expression even when static facial proportions are not an obvious match.

Why an AI score can move with age

An image model compares what is visible now. If facial proportions change, the numerical representation also changes. This does not mean earlier or later results are false; they are comparisons of different images at different developmental stages.

Try age-matched family photos as an experiment

If the family has old photos, comparing a child with a parent's childhood portrait can be an interesting experiment because both faces are closer in developmental stage. It still does not create a genetic test, but it can produce a different visual perspective.

Keep expectations realistic

There is no single age at which a child's “true” resemblance appears. Family appearance is a combination of many traits, and those traits can become more noticeable at different times.