Betsy was the first creature to be named by Syndicate (Tom) in the Land of Mianite on the first day of the players' existence.
Upon visiting the site of Jericho's (Tucker's) future house on top of the mountain, Syndicate discovered the Mountain Cows and their peculiar tendency to stand on top of trees.
But Betsy's existence was short-lived.
Once she was named by Syndicate she was subsequently killed for her leather and beef by Jericho. After his first death, it is believed that Syndicate used the anger from Jericho killing Betsy and from the Enderman that killed him to take up arms against Jericho and commit the first murder in Mianite.