Thanks @Eclipsestar for the last fact!
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-Smallear has been confirmed to be Goldenflower's father.

-Darkstripe didn't choose to be evil, he was only blindly following in Tigerstar's footsteps.

-Bumblestripe loved Dovewing far more than Tigerheart ever could.

-In Fire and Ice and Forest of Secrets there was a cat named Silverpaw who no longer existed by the time Rising Storm came out.

-Goosefeather was made a full medicine cat only after three moons of being trained, meaning that he was a medicine cat at the age of seven moons. (He was made an apprentice at the age of four moons.)