删除json_encode返回中的双引号

Here is my response of

{"success":"1","kids":"[{ StudentId : 1, Student Name : Sampsons Alec},
{ StudentId : 3, Student Name : Craig Jacob},{ StudentId : 4, Student Name : Tumblin Jonathan,}]"}

But i want it as

{"success":"1","kids":[{ StudentId : 1, Student Name : Sampsons Alec},
{ StudentId : 3, Student Name : Craig Jacob},{ StudentId : 4, Student Name : Tumblin Jonathan,}]}

i.e., to remove the double quotes that is in the kids data of the json

How can i do this ?

Note :

return $KidsData;

gives

[{ StudentId : 1, Student Name : Sampsons Alec},
    { StudentId : 3, Student Name : Craig Jacob},{ StudentId : 4, Student Name : Tumblin Jonathan,}]

But When return after json_encode it is adding double quotes like the response i given first.

    $Response = array(
            'success' => '1',
            'kids' => $KidsData
        );
 return json_encode($Response);

How can i fix this ?

Update :

I don't bother if the json becomes invalid