His son, because he's a little Bigger!
or
Only one, but she/he'll have to go out and buy the light bulb adaptor card first, which is extra.
or
The bartender offers him a warm smile and says, "For you, no charge".
or
When it came time to pay, the skunk didn't have a scent, the deer didn't have a buck so they put the meal on the duck's bill.
or