Being a Grandfather is wonderful ~ the best bit is handing the little one an unwrapped creme egg as you help put them in the back of Mummy & Daddy's car for the journey home at the end of their visit to you for tea.
Mummy and Daddy don't usually notice (they are too busy trying to say goodbye to Grandma who is pressing them to take a few cuttings home for their garden) until they get home. The resultant telephone call is best fielded by Grandma whilst you nip off to the pub.
PS In the absence of a Creme Egg I found an unwrapped finger of KitKat worked very well. Fits their tiny hands exactly and it is amazing how far that little chocolate can spread.