Such babies are sweet (5)

I believe the answer is:

jelly

I'm a little stuck... Click here to teach me more about this clue!

'sweet' is the definition.
(jelly is a kind of sweet)

I cannot understand how the rest of the clue works.

(Other definitions for jelly that I've seen before include "Gelignite - something popular at children's parties" , "Wobbly dessert" , "Fruit-flavoured dessert" , "Clear dessert" , "It wobbles" .)

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app