Code:
/cast [mod:ctrl,mod:shift,nomod:alt target=ToonA];[mod:ctrl,mod:alt,nomod:shift target=ToonB];[mod:alt,mod:shift,nomod:ctrl targer=ToonC];[mod:ctrl,mod:alt,mod:shift target=ToonD]; heal spell here
something along this line would work. Haven't tested it not sure if the syntax is correct