Extended family
Beyond direct parents: siblings, grandparents, twins, adoption. The science behind resemblances that skip a generation or diverge within siblings.
Resemblance is not limited to the parent-child triangle. A large part of striking family resemblances actually concerns siblings (brothers and sisters who look alike or not at all), grandparents ("skipped generation" effect), twins (identical or fraternal), and special cases like adoption or social perception of resemblance.
This category explores these less obvious configurations. Why can two children of the same parents look very different? Because each receives a random combination of half of the parental alleles — the math gives 1 in 70 trillion chance of having two genetically identical children (excluding identical twins). Why can a child be the spitting image of a grandparent they never knew? Because of recessive genes hidden in the parents.
We also cover resemblances that have nothing to do with genetics: couples who end up looking alike, adoptive families where perceived resemblances are partly social. Science is clear: resemblance does not define the family bond.
5 articles
Why Don't Siblings Always Look Alike?
Same parents, very different faces. Why? Genetic recombination, epigenetics and the "sibling lottery".
"It Skips a Generation": Myth or Genetic Reality?
My child looks more like their grandparent than their parents: real phenomenon or illusion? Science answers.
Identical vs Fraternal Twins: Why the Differences?
Why aren't identical twins 100% identical? Why can fraternal twins look completely different? The science of twins.
Adoption: Why You Sometimes "Look Like" Your Adoptive Parents
"He really looks like you!" — when there's no genetic link. Three mechanisms documented by science.
Family Resemblance: Myths and Facts
We often hear "you're the spitting image of your mother." But what does science actually say about family resemblance?
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