How to insert an element in multidimentional array in Javascript [closed]

I want to create the bellow array from user inputs:

myArr = [
    parantArr1[
        childArr1[
            'user input1'
            'user input2'
        ],
        childArr2[],
        .....
     ],
     parantArr2[
         .....
     ]
]

My code is as bellow:

myArr=[];
myArr.push(new Array('parant1'));
myArr.push(new Array('parant2'));
myArr[0].push(new Array('child1'));
myArr[1].push(new Array('child2'));

myArr[0][0].push('user input1');
myArr[0][1].push('user input2');

Why the code is not working?
The out put is

myArr[[parant1,[child1]],[parent2,]]