diddums!

剑桥词典

something you say to show that you feel no sympathy for someone who is behaving like a child
（用於表示對行事孩子氣的人不感到同情）
He called you a bad name , did he? Ah, diddums! 他罵了你，是不是？哎喲，真可笑！ 返回 diddums!