Struggling with Wherefore Art Thou challenge

Hello Campers,

This is my first post on this forum I hope you’ll help me.
I got stuck and can’t go further :frowning:
The code is below.
Kuba

function whatIsInAName(collection, source) {
  var arr = collection.filter(function (source){
    for (var i = 0; i < collection.length; i++){
           if ( collection[i].hasOwnProperty(source) ){
          console.log(collection[i]);
          }
        }
      });
return arr;
};

whatIsInAName(
  [ { first: "Romeo", last: "Montague" }, //0
    { first: "Mercutio", last: null }, //1
    { first: "Tybalt", last: "Capulet" }], //2
    { last: "Capulet" });