Against all odds, a beloved member of a Malden family is back home, after almost four months missing. Udon, a 10-year-old Maltese who disappeared from his owners’ fenced-in backyard in June, turned up on Oct. 14, and is now back with the people who never gave up on getting him back. “I couldn’t believe my eyes,” said owner Ming Tseng, who received a picture of Udon and a message that he was safe in Weymouth. “I knew it was him. The way that he looked in the picture, his expression, I knew. I sent it to my family, they were like, ‘That’s Udon.’ I sent it to my friend, he was like, ‘Even I know that’s Udon.’” Where Udon was all that time remains a mystery. Tseng says the man who contacted her, and eventually made good on his promise to return Udon, claimed to have found him far from home some time ago, and only recently learned an identical dog was missing in Malden. “What he said was maybe a month ago he found him in downtown Boston,” said Tseng, who doesn’t think Udon could have made it so far of survived so long on his own. “I 100-percent believe that he was picked up by someone, ever since the first day.” Tseng never once gave up on finding Udon, plastering the neighborhoods in Malden and Melrose around her house with missing posters, making the rounds at the Victorian Fair in Melrose, and spreading the word online in every venue she could think of.