If you are thinking about giving your cat a cherry, make sure you remove the seed before your give it to them.
Although cherries are not harmful to cats, you should not give them a lot at a time. Cherries can cause your cat to have a stomach ache, and can make your cat sick if it has too many.
Cherries do contain cyanogenic glycosides which will result in cyanide poisoning. Although in small quantities, it will not harm your cat, in large quantities it can do your cat harm.
If your cat has already eaten cherries, you dont need to worry too much. If your cat eats the seed form a cherry, you should take it to the vet asap.
It is not a good idea to do what this cat owner did.
If you give cherries, make sure you wash them, take the seed out, and only give your cat a small amount.