Small baby, on paper, is most cute (8)
I believe the answer is:
sweetest
'most cute' is the definition.
'small baby on paper' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'baby' becomes 'wee'.
'on' means one lot of letters go next to another.
'paper' becomes 'test' (**).
's'+'wee'+'test'='SWEETEST'
'is' is the link.
(Other definitions for sweetest that I've seen before include "Most saccharine or dulcet" , "most agreeable" , "Most Melliflous" , "'''Success is counted ...by those who ne'er succeed'' (Emily Dickinson) (8)'" , "Most winsome" .)