findOne not executed - node.js

Question

I have the code below:
exports.getMyPets = function (req, res){
var email = req.body.email;
var result = [{}];
Owner.findOne({"email" : email }, "_id", function(err, owner){
if(err)
res.send(err);
console.log("Owner: " + owner._id + "\n");
Pet.find({"OwnerId": owner._id}, function(err, pet) {
if(err)
res.send(err)
var index = pet.length;
var empty = false;
if(index > 0)
empty = true;
try{
for (let x = 0; x < index; x += 1){
PetPicture.findOne({"petId" : pet[x]._id}, function (err, petPic){
console.log('pet ID: ' + pet[x]._id);
result[x] = {
name: pet[x].name,
breed: pet[x].breed,
description: pet[x].description,
imageType: petPic.imageType,
imageData: petPic.imageType
};
}); //end of petPicture.findOne
console.log('X : ' + pet[x]._id);
}// end of for loop
} catch (error){
console.log(error);
}
}
while(true){
if (result.length === index)
break;
}
if(!empty){
res.json(pet);
} else {
res.json(result);
}
}); // end of Pet,find
}); // end of petOwner.findOne
};
The block of PetPicture.findOne (the whole try catch block) does not get executed when I try to call it on endpoint. It does not log anything, not even an error on the catch part. What can I do to debug this?