LOL... the way this thread has run has made me think of a story... my sis in law #4 (I have 4) and I were sitting watching some of our children (2 of her toddlers and two of mine) playing on the shingle at the side of the grass (in a farm house yard - not by the road!).

Sister-in-law #1 had just had her first baby and was going on about keeping baby's things clean.
SisInLaw#4 said to me quietly some thing like... "you know, when you have your first baby you steralise everything, even their thumbs if you could... but you get to number 3 or 4 and you see them sitting on the driveway eating dog-s**t, and you think ... pah, thet'll be alright"

Of course, we didn't let the kids eat dog-do, but the sentiment was the same... maybe thats why our kids who ate heaps of dirt and grass and goodness knows what else, are very healthy and rarely get sick? Great immune systems been fostered there!

Kiwi... just thinking about your recent bout of illness that frustrated you so... maybe I need to box up some dirt for you to eat - maybe the British soil and air is lacking some inherant Kiwi goodness!