Technically a woman can have twins by two different fathers. There are two types of twins. Identical twins are born of the same egg, splitting after fertilization. Twins that are not identical are born when more than one egg is released, and both are fertilized.
In real life, however, sometimes siblings closely resemble each other, even if they have differnt fathers, or even different mothers. It depends entirely on genotypes and phenotypes- or which genetic material is a) passed on and b) dominant.
Edited by LadyCFII (10/24/06 03:39 PM)
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Why is it that if someone tells you that there are 1 billion stars in the universe you will believe them,
but if they tell you a wall has wet paint you will have to touch it to be sure?