I'm at my wits end and don't know what to do so seeking wisdom here.
Always had cats but I've never had a Tom that regularly sprays inside. To avoid drip-feeding and give you a proper picture, he's nearly 7, there's just him and his brother cat-wise in the house (who doesn't spray), and he sprays when he's unsure/nervous/doesn't know what to do, even when it's as simple as 'should I lie down or patrol the kitchen again?' type decision. Been to the vets and not a urinary tract or medical problem.
Over 50% of the time it's phantom spraying and nothing comes out, and sometimes it's like what he's just done and it's like he's emptied his whole bladder 
Always had Feliway, always had a safe space for their food and (lots of) clean litter, a tall cat tree so they have a 'safe' space away from the toddler etc. We've got a second baby on the way and just finished some major building work to the house and it was considerably worse during that period (understandably), but it's suddenly picked up again and I don't know what else to do to discourage it or stop it from getting worse
Any hints? Any advice would be hugely welcome!