BILLY AND BOBBY'S GREAT GRANDMAS

Billy's great grandma is nearly ninety three
Hearing is failing and can hardly see 
Still makes Billy a lovely cup of tea 
Her philosophy is whatever will be will be

Bobby's great grandma is so much fitter
The same age as Billy's knows all about Twiiter
Has a hundred or so friends on Facebook too 
Making a cup of tea though she hasn't a clue

So the question I ask which great gran is best
A bit of both is what I would probably suggest
If I reach the age of Billy and Bobby's great gran
I will consider myself to be a fortunate man