My wife was speaking to someone at work recently who had just had a baby. She was disappointed to have delivered by caesarian section, because it meant she couldn't walk with the pram down Baxtergate collecting money, at least until the wound had healed a bit.
It seems that people, these days often old ladies, will put a coin into the hand of a newborn baby as it passes in the pram. It is meant to make sure that during its life the child shall never want for money. In Edinburgh it is known as 'silvering the baby' and often in the past a siver sixpence was used. Sometimes it was placed under the pillow or a blanket, possibly because it was less likely to be swallowed there.
Similarly a purse should never be given as a gift unless a coin is placed in it first, presumably ensuring it shall never be empty. In Scotland this is known as hanselling the purse. As long as the hansel was left in the purse, others would join it.
Also a knife should never be given without money being paid for it, traditionally the smallest coin of the realm. A promise that the knife would never be used against the giver, called by some 'blunting the knife'. Interestingly the Horngarth or Penny Hedge should rightly be made of sticks cut with a knife purchased for a penny.
Silvering the baby is still carried out in Scotland, Wales and Ireland. In England it seems to be restricted primarily to the north, although it has been reported from as far south as Surrey in the 1950s. Of course these days a 50p or £1 coin is the currency of choice. To a certain extent the connection between silver and babies has been commercialised. A quick look in a high street jeweller's will reveal silver piggy banks, silver spoons and other tacky trinkets.
At least the tradition still flourishes in Whitby. Indeed one mother came home with at least £50 from her first stroll out with the bairn. Still, mum's the word, eh?