False. The probabilities are 50/50. In genetics, genes get passed down as far back as grandparents. Here's an example-- it's a human example, but in this case, it still applies:
Bob has blue eyes. Both of his sisters, however, have brown eyes.
Bob's father has blue eyes, but his mother has brown eyes. How did that happen? Blue eyes is a recessive gene, and brown is dominant. Explanation, without even seeing Bob's maternal grandparents: One of his mother's parents has blue eyes, the other has brown. When Bob's mother contributed the ova carrying Bob's prospective DNA, she just happened to pass on an ova carrying the gene for blue eyes, rather than brown. For Bob's sisters, their mother passed on ova carrying the gene for brown eyes, for each of those children. Odds are 50% that another child may have also had blue eyes.
Now let's look ahead to the future: Tom has blue eyes. He married a woman who not only has brown eyes, but so do her parents, and grandparents, and all previous generations. The only gene she has to contribute is brown eyes. And blue being recessive, the only gene Tom has to contribute is blue. All of their children will be born with brown eyes, but they will also carry the gene for blue eyes in some of their gametes. Even if they marry someone else with blue eyes, there is no guarantee that any, if not all, of their children will have blue eyes-- the odds are 50% for each child. However, if they marry someone with brown eyes, it depends on what color the spouse's parents' eyes are. If the spouse carries a gene for blue eyes, contributed from the children's grandparent, there is a 25% chance they could have a child with blue eyes. If the spouse only carries genes for brown eyes, all of the children will have brown eyes, no matter what-- but one or all of them could still carry the gene for blue eyes.
I hope that makes sense. Genetics is a rather complicated subject for anyone to understand.
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