Here's what rhymes with protheir.
                        
                        
                    
                                their  there  fair  hair  share  fare  faire  hare  cher  fere  sehr  where  care  bear  chair  pair  rare  wear  affair  bare  dare  spare  swear  tear  mare  stare  ware  flare  mer  pear  scare  snare  stair  flair  guerre  lair  mehr  affaire  mair  pare  thair  aware  square  prayer  prepare  repair  unfair  glare  thoroughfare  blare  repairer  coheir  funfair  declare  despair  unaware  beware  forbear  impair  earthenware  aftercare  bugbear  curare  ensnare  horsehair  midair  forswear  parterre  chinaware  overbear  spyware  tinware  eldercare  beachwear  broodmare  backstair  ovenware  everywhere  anywhere  compare  underwear  debonair  disrepair  solitaire  billionaire  dinnerware  foursquare  maidenhair  outerwear  ironware  legionnaire  debonaire  foreswear  camelhair  wirehair  millionaire  doctrinaire  silverware  tableware  medicare  kitchenware  millionnaire  setsquare  questionnaire  commissionaire  concessionaire  extraordinaire  multimillionaire  Words that almost rhyme with protheir
cell  fell  sell  hell  shell  celle  sel  well  tell  del  bell  smell  gel  spell  swell  tel  dell  delle  nel  yell  belle  weal  bel  knell  nell  telle  resell  jell  hotel  dwell  excel  repel  befell  gaol  nouvelle  propel  quell  gazelle  lapel  quel  retell  morel  novelle  outsell  noel  parallel  personnel  farewell  dispel  expel  cartel  foretell  motel  unwell  impel  pastel  carousel  caravel  undersell  nacelle  carrousel  oversell  compel  citadel  infidel  decibel  organelle  photocell  bagatelle  misspell  muscatel  clientele  mademoiselle  materiel  fontanelle  commonweal  tagliatelle  nonparallel  zinfandel  antipersonnel  therefor