Variance (random effects)
Covariance (spouse-spouse)
Covariance (sibling-sibling)
Covariance (parent-child)
Genetic, family and childhood model
σ
g
2
+
σ
f
2
+
σ
c
2
σ
f
2
1/2
σ
g
2
+
σ
f
2
+
σ
c
2
1/2
σ
g
2
+
σ
f
2