[Idiom] Too little of something is too much.

[jiaruchan]

If parents does not allow their son to watch TV at anytime, can I say 'When is too little of something too much' to mean the parents should allow some TV watching for the son?

 

[sarat_106]

If parents does not allow their son to watch TV at anytime, can I say 'When is too little of something too much' to mean the parents should allow some TV watching for the son?

No, it does not convey anything, You can say:
Allowing too little watching of TV to children can be as bad as too much.

It means: Allowing too little watching of TV to children is equally bad as allowing too much watching.