ondine, x-ii-xiii

Ulysses had a two-year-old dog, Argos, that he had to leave behind when he sailed off to Troy. When he finally returned, 20 years later and disguised by Minerva as a decrepit beggar, an old hound at his threshold lifted his head and wagged his tail upon hearing his long-lost master's voice. Ulysses turned his face and wiped a tear away as the old dog died, happy at having fulfilled his final duty of welcoming his master's return.

That's from one of the earliest works of Western literature.