Had to keep the basement door closed while we fixed the plumbing
downstairs - that's where the litterboxes are. We brought one
upstairs.

Fixed the plumbing, basement is open, Louis is acting totally psycho.

This just appeared out of nowhere, and its first indication was a
couple weeks ago.

He is now spraying everywhere - walls, doors, everywhere. And it's no
longer a "spraying" posture, he's squatting like he's just
eliminating.

Five days ago he was seen by our vet, who poked a needle into his
bladder to check his urine - all seemed well.

We have two Feliway diffusers in the house. He gets tons of play time.
He gets walks outside. Tiger seems unaffected.

The only advice I've seen that comes from reputable sources, beyond
what we're already doing, suggests keeping him cloistered and slowly
reintroducing him to the rest of the house.

Gah. He's a racehorse - this'll be a major PITA - he hates being
inactive or alone.

BLink