Du Zichun
... that in Ryūnosuke Akutagawa's retelling of the Tang dynasty short story "Du Zichun", a son grieves for his mother who has been reborn as a horse?
... that in <a href="./Ryūnosuke_Akutagawa" id="mwBDk" rel="mw:WikiLink" title="Ryūnosuke Akutagawa">Ryūnosuke Akutagawa</a>'s retelling of the <a href="./Tang_dynasty" id="mwBDo" rel="mw:WikiLink" title="Tang dynasty">Tang dynasty</a> short story "<b id="mwBDs"><a href="./Du_Zichun" id="mwBDw" rel="mw:WikiLink" title="Du Zichun">Du Zichun</a></b>", a son grieves for his mother who has been reborn as a horse?