Perhaps one of our neighbours led parent astray (3,6)
I believe the answer is:
red planet
'perhaps one of our neighbours' is the definition.
(one of Earth's neighbours)
'led parent astray' is the wordplay.
'astray' indicates anagramming the letters.
'led'+'parent'='ledparent'
'ledparent' anagrammed gives 'RED PLANET'.
(Other definitions for red planet that I've seen before include "Colourful description of Mars" , "Mars is colourfully known as the . . . . . . . . ." , "one of our neighbours" , "Informal name for Mars" , "object in 21 [SPACE]" .)