Where's My Cow? by Terry Pratchett

Every day, Commander Vimes of the City Watch would be home at six o’clock sharp to read to Young Sam, who was one year old.
Six o’clock, no matter what…
or who…
or why…
because some things are important. (WMC)

‘Never try to milk a chicken.  It hardly ever works.’ (WMC)

Why is Young Sam’s nursery full of farmyard animals anyway?  Why are his books full of moo-cows and baa-lambs?  He is growing up in a city.  He will only see them on a plate! They go sizzle! (WMC)

‘I fink, derefore I am.  I fink.’ (WMC)

‘…Are we not all, in some way, looking for our cow?’ (WMC)