The Guardian's Gambit - The Felinity Chronicles, #1

Life for a group of cats changes after a new kitten is brought into their family. Shaman is a Conjurepurr, one of a long-forgotten tradition of feline sorcerers. His arrival unlocks hidden mysteries and unleashes ancient nightmares on their peaceful home. Forced to battle terrifying monsters, the likes of which no kitty has faced in centuries, the cats struggle to discover the true nature of Shaman's powers, all while avoiding the ancient beings seeking to destroy them.
Along the way, the cats must learn to set aside their differences and work together as a team. Their very survival depends on it. But with spirits, monsters, and even fellow cats conspiring against them, will they run out of time?