#microchimerism

Sibling or fetomaternal* cell sharing happens through the (fused) placenta, but i think it's maybe possible that the wandering cells would make it to the skin, as they are often stem cells. But honestly i have no idea if they could be 'right' type of stem cells, aka those that can differentiate into melanocytes.

*between the offspring and the mother. Your cat's mother evidently has the pink allele, so this would work just as well for you.

A sometic mutation (B on the figure above) would be for example her losing the wild type copy in an early cell, and thus exhibiting only the remaining pink allele. I think i'd chose this method for my semi-realistic fictional pink-streaked cat.

During pregnancy, fetal cells migrate out of the womb and into a mother’s heart, liver, lung, kidney, brain, and more. They could shape moms’ health for a lifetime, Katherine J. Wu reports. The presence of these cells, known as microchimerism, is thought to affect every person who has carried an embryo, even if briefly, and anyone who has ever inhabited a womb. The cross-generational transfers are bidirectional—as fetal cells cross the placenta into maternal tissues, a small number of maternal cells migrate into fetal tissues, where they can persist into adulthood. ⁠

“When pregnant, the cells of the baby migrate into the mothers bloodstream and then circle back into the baby, it’s called “fetal-maternal microchimerism”.⁠ For 41 weeks, the cells circulate and merge backwards and forwards, and after the baby is born, many of these cells stay in the mother’s body, leaving a permanent imprint in the mothers tissues, bones, brain, and skin, and often stay there for decades. Every single child a mother has afterwards will leave a similar imprint on her body, too.

Even if a pregnancy doesn't go to full term or if you have an abortion, these cells still migrate into your bloodstream. Research has shown that if a mother's heart is injured, fetal cells will rush to the site of the injury and change into different types of cells that specialize in mending the heart.

The baby helps repair the mother, while the mother builds the baby. This is often why certain illnesses vanish while pregnant. It’s incredible how mothers bodies protect the baby at all costs, and the baby protects & rebuilds the mother back - so that the baby can develop safely and survive.

Think about crazy cravings for a moment. What was the mother deficient in that the baby made them crave? Studies have also shown cells from a fetus in a mothers brain 18 years after she gave birth.

If you’re a mom you know how you can intuitively feel your child even when they are not there….Well, now there is scientific proof that moms carry them for years and years even after they have given birth to them.

Naturally Acquired Microchimerism

http://www.catholic365.com/article/5825/what-jesus-and-mary-shared.html

Minarabymic: a term for those who have microchimerism, but it is nevertheless an important part of their identity for one reason or another. The term comes from the Akkadian phrase Mina rabûm, which translates into English as "something more." Akkadian (Assyro-Babylonian) is an ancient East Semitic language used in Mesopotamia (modern Iraq and Syria) from the 3rd millennium BCE to the 1st millennium CE. It was the language of communication, culture, and diplomacy in the Akkadian Empire, Babylonia, and Assyria, using cuneiform for writing. The language ceased to be used by the 8th century BCE, giving way to Aramaic.