Three Smiling Kittens in Their Bed

About this drawing

Three kittens in a bed can be brothers and sisters and still look nothing alike. One may be striped, one spotted and one a single solid color. It seems surprising, but it is very common in cats, and the reason is fascinating.

Every kitten gets its own mix of genes from its parents, and that mix is different each time. There is another twist as well. If a mother cat mates with more than one male during the same cycle, kittens in one litter can have different fathers. So two siblings born on the same day may only be half related.

Coat colors hold other surprises. Calico and tortoiseshell cats are nearly always female, because the genes for orange and black fur sit on the X chromosome. Orange cats, on the other hand, are more often male. And a white kitten may be hiding other colors in its genes.

However different they look, littermates grow up as a team. They wrestle, chase each other's tails and learn how hard is too hard to bite. If one chomps down, the other squeals and stops playing, and that is a lesson that sticks. At night, they pile together to stay warm. That little gang is really a kitten's first classroom.

• kittens
• litter
• siblings
• toys