My DS (nearly 4) loves watching this programme so I have satisfied myself with watching it purely to analyse what a perculiar household they are.
T&T's mother is either a secret alcoholic or is sniffing something in the kitchen cupboard...she is far too perky, jolly and relaxed to be a real mother of two active children.
She also seems to be suffering from some kind of cleanliness OCD, which is probably where Tim gets his neurotic/anxious side from. In my son's favourite episode they have Mossy the Dog (who belongs to hip modern grandmother Jean) for the day.
Tim put a bowl of water down for the dog and is then immediately instructed to "superwash your hands now" because he has touched the bowl. Tony Welch comes round to play and he and Topsy watch as Tim gives Mossy a dog biscuit. After which his mother instructs that ALL THREE OF THEM must now "go and double super wash" their hands. At this point the dog rolls a toilet roll down the stairs and Mummy grabs it, rolls up the bit that has come unravelled and rushes off to the kitchen saying "I'll have to throw this WHOLE toilet roll away now!"
Next they all get ready to take the dog for a walk and Mummy crouches down at Tim's eye level and says very earnestly "Now do you have the DOG POO bags that Grandma brought round Tim?". Tim looks all anxious and earnest back and rushes off to find them. Clearly an ASDA carrier bag isn't an option and no doubt the bags come with their own sterile gloves attached.
Major calamity then ensues when the phone rings, Mummy has to get it and - horror of horrors - the dog runs onto the next door garden and DOES A POO. You can virtually see Mummy hyperventilating as she says "GET ME THE POO BAG TIM!!!" and rushes off. Next minute she is back, insists they all go back inside (I think she needs to sit down to calm her nerves with something) and Mummy announces that she must now go and wash her hands (no doubt a double super double treble wash).
No wonder poor Tim can't even cope with wearing a new pair of jeans....