In the Wind by K. Sterling

Welcome back to Lake Cliff, a quiet yet inexplicably dangerous suburb of Chicago. When we last visited our heroes, they were calmly and cozily settling into their happily ever afters. Unfortunately, Lavender and Aiden’s brisk yet peaceful morning run through the woods is interrupted by a loud explosion. They return to Holderson Manor to find that Sage has been abducted by a dangerous enemy from Lavender’s past.
With Sage in the wind, it quickly becomes a race against the clock to bring him home. Lavender has assembled a team of friends and allies when Captain Denver Walsh arrives with the missing piece of the puzzle. A tortured and traumatized vet, Denver offers a grim solution only to find himself drawn into the mission and a new family as a British lord, an FBI agent, a Russian hacker, a few cops and a forensic psychologist join forces to hunt a killer and find Sage before it’s too late.
Sometimes, the monsters in our heads are just as dangerous as the ones waiting under our beds and hidden deep in the forest. Our team quickly learns that Denver needs their help almost as urgently as Sage. Aiden looks to a new friend for backup when he realizes he’s in way over his head. Meanwhile, Sage has to make peace with the monster in his head and the one that’s been sleeping in his bed as he struggles to survive. Sage is in for a brutally intense fight but he’s determined to outwit and outlast the horror hunting him and find his way home to his son and the man he loves.