Hey Denise,
The color of the short tail, will depend a lot on the sire and dam of the off spring, with some animals taking on the color of either of the 2 parents or both. So to say whether it will darken or lighten would be difficult to say as color is contingent on several factors, and depends heavily on the inherited traits for color of the off-spring from its parents. Some animals will be intermediate in color exhibiting a range of color between both parents or showing a dominant trend toward one color over the other. Hope this helps!
Angel
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In the theater of my life, this pickle has no goal!!