Are Cousins Born from Twins Siblings?

Since identical twins share the same DNA, and both parents are identical twins, genetically, the kids are siblings even though they are actually cousins.

Are twins babies cousins or siblings?

Since identical twins share the same DNA, the children of two pairs of identical twins are legally cousins, but genetically more similar to siblings.

How related are cousins from twins?

Instead of half of one chromosome from each pair, they would on average share around one quarter. This is why first cousins share around one-eighth or 12.5% of their DNA.