MongoDB models relationships in Laravel

Question

this is Post model data:

{
   "_id" : ObjectId("58bb1293534e2028d0006f33"),
   "body" : "Some body",
   "comments" : [
       {
          "commentID" : "58bb115c534e2028d0006f2d"
       },
       {
          "commentID" : "58bb1153534e2028d0006f2c"
       }
    ]
}

this is Comment model data:

{
   "_id" : ObjectId("58bb1153534e2028d0006f2c"),
   "message" : "Some Message"
},

{
   "_id" : ObjectId("58bb115c534e2028d0006f2d"),
   "message" : "Another Message"
}

how to set relationship between these models by jenssegers-mongodb package?