A small amount like that shouldn't hurt them.  Isn't it the lactose in milk
some cats have a problem with?  Cream would be more fat and less sugar than
milk.

I've had only one cat ever that did not take to cream.

Cats are like people: some become lactose intolerant, due to loss of the
enzyme necessary to properly metabolize lactose. It travels into the
large intestine, where bacteria break it down, generally causing lower
GI problems.

It varies among people of different background, but roughly 1/3 of
adults become lactose intolerant. I have no idea if it's more common in
cats. In humans, it can occur anywhere from newborn to the elderly, but
mostly occurs from later teens to early middle age. Once a human passes
middle age without becoming lactose intolerant, they are less likely to
develop it later in life.

Watch for common symptoms: gas (think really stinky kitty farts)
diarrhea, or loose stool, and possibly vomiting.

Small amounts of cream, as you described, may be well tolerated,
especially if after a regular meal. HTH.

~~~~~~~~~~~~
"Life without cats would be only marginally worth living."
-TC, and the unmercifully, relentlessly, sweet calico kitty, Kenzie.

How you behave towards cats here below determines your status in Heaven.
- Robert Heinlein

Life is very difficult. Once you understand that, life becomes easier.
-Buddha

Both of my kitties used to get a small (soy sauce sized - approx 1 tbsp)
bowl of cream or milk every day since they were kittens.
Gossamer stopped drinking it several years ago but Jeeves demands
"Meowk!" every morning (actually every time I'm anywhere near the
refrigerator!)

I recently read that the higher the fat content, the less lactose it
has.  So cream should be better tolerated than milk.

Smokey gets half & half (10% cream) when I have my coffee. She usually lets
it go sour before she drinks it. Cali can't stand it either way.

I take it you have been living under a rock.

Cats and cream, like mice and cheese, is an association so old that it
is part of the folk memory - it certainly goes back at least to the
middle ages, but more probably back to shortly after the first
association between cats and milk drinking humans.  It is assumed, and
treated as universally known in fairy tales.

I get good results with half and half (half milk and half cream) - the
cats love it and don't seem to have problems tolerating it.