there are probably many reasons for this to be still happening... one would be medical... also in my experiences boys tend to take longer in training... i tend not to agree with pull ups as they tend to prevent the child from being uncomfortable with the sensation of bowel movements etc. again, its a process that takes effort by parents and care providers... working together to ensure same things are followed through... also at this age, talking to the child about simply... how its easier for them in toilet, cleaner, faster... etc... make sense of it for them. i have 2.5 year old in my care trained through night and everything as a result of open communications with parents and working with the child... children also refuse to go based on fears, or that constipation previously hurt them... they get caught up in activity and dont want to stop what they are doing as well... be consistent and firm. use others bathrooming as a tool... everyone is doing this, you have no choice but to try... keep it simple but be firm. i did an interview two days ago, the mom's 4 year old had no bathrooming skills... that unfortunately is part previous care provider, part parenting... good luck... oh and for the smelliness... yes somedays you want to throw up! i had children who were vegetarian due to allergies etc that omg... good luck!!!