udder duder udder duder dduer dduer udedr duedr ueddr euddr deudr edudr udedr duedr ueddr euddr deudr edudr ddeur ddeur dedur eddur dedur eddur uddre dudre uddre dudre ddure ddure udrde durde urdde rudde drude rdude udrde durde urdde rudde drude rdude ddrue ddrue drdue rddue drdue rddue uderd duerd uedrd eudrd deurd edurd udred dured urded ruded drued rdued uerdd eurdd uredd ruedd erudd reudd derud edrud dreud rdeud erdud redud uderd duerd uedrd eudrd deurd edurd udred dured urded ruded drued rdued uerdd eurdd uredd ruedd erudd reudd derud edrud dreud rdeud erdud redud dderu dderu dedru eddru dedru eddru ddreu ddreu drdeu rddeu drdeu rddeu derdu edrdu dredu rdedu erddu reddu derdu edrdu dredu rdedu erddu reddu
Note: these 'words' (valid or invalid) are all the permutations of the word udder. These words are obtained by scrambling the letters in udder.