Writes to pal to arrange toy for child (5,6)
I believe the answer is:
water pistol
'toy for child' is the definition.
(water pistol is a type of toy)
'writes to pal to arrange' is the wordplay.
'arrange' indicates an anagram.
'writes'+'pal'+'to'='writespalto'
'writespalto' anagrammed gives 'WATER PISTOL'.
(Other definitions for water pistol that I've seen before include "harmless weapon?" , "Small bomb" , "Plaything" , "Fun gun?" , "Source of aggressive jet" .)