Sickly, the elder of Elimelech the Bethlehemite’s two sons by Naomi. He married Ruth and died childless (Ruth 1:2, 5; 4:9, 10), in the land of Moab.
Mahlon
Mahlon was one of two sons of Elimelech and Naomi, who left Bethlehem during a famine and settled in Moab. There he married Ruth, a Moabite woman, and there he died, along with his brother and his father, leaving Naomi alone. His name returns at the end of the story, when Boaz tells the elders at the gate that he has bought Elimelech’s land and has taken Ruth, “the wife of Mahlon,” to raise up the name of the dead on his inheritance. Mahlon never speaks, yet the whole book of Ruth turns on his loss.
4 verses
Ruth
And the name of the man was Elimelech, and the name of his wife Naomi, and the name of his two sons Mahlon and Chilion, Ephrathites of Bethlehemjudah. And they came into the country of Moab, and continued there.
And Mahlon and Chilion died also both of them; and the woman was left of her two sons and her husband.
And Boaz said unto the elders, and unto all the people, Ye are witnesses this day, that I have bought all that was Elimelech's, and all that was Chilion's and Mahlon's, of the hand of Naomi.
Moreover Ruth the Moabitess, the wife of Mahlon, have I purchased to be my wife, to raise up the name of the dead upon his inheritance, that the name of the dead be not cut off from among his brethren, and from the gate of his place: ye are witnesses this day.
From Easton's Bible Dictionary
Matthew George Easton, 1897