My Cat, Gretzky

My old cat has vanished. He is 19 years old. Older than me by 3 years. He was respected by our much bigger dogs, the other cat, and by the humans too. He had some real leadership skills, that's for sure, and he was calm, sweet, and easy-going. Recently he was getting confused and demanding. He meowed constantly for food but he stayed scrawny despite being well fed. He vanished a few days ago after sneaking outside. No one has seen him. We looked, and put up signs, but we think that he probably decided it was time to go. I hope he gets a big rat in cat heaven.