Most angelic son facing little ordeal (8)
I believe the answer is:
sweetest
'most angelic' is the definition.
('sweet' can be a synonym of 'angelic')
'son facing little ordeal' is the wordplay.
'son' becomes 's' (genealogical abbreviation for son).
'facing' says to put letters next to each other.
'little' becomes 'wee' (similar in meaning).
'ordeal' becomes 'test' (a testing situation).
's'+'wee'+'test'='SWEETEST'
(Other definitions for sweetest that I've seen before include "dearest" , "having most sugar" , "Most saccharine or dulcet" , "'''Success is counted ...by those who ne'er succeed'' (Emily Dickinson) (8)'" , "Most sugary or most mellifluous" .)