There's nothing about mother following a beast (6)
I believe the answer is:
animal
'beast' is the definition.
(a beast is an animal)
'there's nothing about mother following a' is the wordplay.
'there's nothing' becomes 'nil' (nil means a score of zero in football).
'about' means one lot of letters goes inside another.
'mother' becomes 'ma' (ma can mean mother).
'following' says to put letters next to each other.
'nil' going around 'ma' is 'nimal'.
'nimal' put after 'a' is 'ANIMAL'.
(Other definitions for animal that I've seen before include "' - - Farm', Orwell" , "Circus performer, maybe" , "Uncivilised person" , "Creature having voluntary movement" , "Source of meat" .)