Mom gives color to the boys and girls, dad gives color to the girls only. The color gene is carried on the X, not the Y. Females are XX - Males are XY
With her mating with more then one, each kitten could have a different father. If the father of the red one is the red tom, then it could be either male or female, depending on whether he gave the kitten and X or a Y
. But if the father is the brown tabby, then the red kitten would be a male (color from the mom).
Are they the only 2 kittens she had? The red tabby and the brown tabby?
BTW Sully, if you want to learn about cats, then its also nice to learn the proper "color" names too.....