A Melbourne woman hit her daughter-in-law with a hammer 33 times, killing her so her son would be free to marry someone else.
Huajiao Zhuang, 50, sobbed and wailed after a Victorian Supreme Court jury found her guilty of the 2012 murder of 21-year-old Dan "Selina" Lin, rejecting her claim she acted in self-defence.
Her trial was told Zhuang had a continuing feud with her daughter-in-law over the respect Lin paid to her.
Prosecutor Peter Kidd said Zhuang wanted her son Peter to divorce Lin and marry a woman from China so he could earn "hundreds of thousands of dollars" from the woman's family, thanks to his permanent Australian residency.
A school friend of Lin once heard Zhuang ask her grandson "how would you like to change your mother?", Kidd told the trial.
Kidd said Zhuang, of Reservoir, went to Lin's home at Bundoora in May 2012 and struck her 33 times with a hammer.
Zhuang put Lin's body in a nylon bag, placed it in a wheelie bin and later that night returned to dump the body in a nearby creek, he said.
Zhuang later told police a dispute over her grandson's bath water sparked the fatal fight.
Defence lawyers argued Zhuang had acted in self-defence and it was Lin who started the fight and produced the hammer.
But the jury on Thursday found Zhuang guilty of murder.
Zhuang wailed loudly after the verdict was delivered, and had to be physically assisted to leave the courtroom.
Justice Stephen Kaye will hear sentencing submissions next Thursday.