Overtake father with two sons (4)
I believe the answer is:
pass
'overtake' is the definition.
(as in passing on a road)
'father with two sons' is the wordplay.
'two sons' can mean two substitutions for 'sons'.
'father' becomes 'pa' (pa can mean dad or father).
'with' says to put letters next to each other.
'sons' becomes 's'.
'sons' becomes 's'.
'pa'+'s'+'s'='PASS'
(Other definitions for pass that I've seen before include "Get beyond" , "complimentary ticket" , "Elapse, go by" , "degree?" , "sticky situation if one is pretty" .)