public class Test_EmbeddedObjects {

    class Item : RealmObject {
        public string? Label { get; set; }
        public ChildItem? ChildItem { get; set; }
        public IList<ChildItem> ChildItemList { get; } = null!;
        public IDictionary<string, ChildItem> ChildItemDict { get; } = null!;
    }

    class ChildItem : EmbeddedObject {
        public string? Label { get; set; }
    }

    public static void Main() {
        var config = new InMemoryConfiguration( "meemoo.db" ) {
            Schema = new Type[] { typeof( Item ), typeof( ChildItem ) }
        };
        var realm = Realm.GetInstance( config );

        var item = new Item { Label = "A" };
        item.ChildItem = new ChildItem { Label = "b" };
        realm.Write( () => {
            realm.Add( item );
            item.ChildItemList.Add( new ChildItem { Label = "c" } );
            item.ChildItemDict.Add( "d", new ChildItem { Label = "d" } );
        } );

        Console.WriteLine( item.ChildItem.Parent != null); // False
        Console.WriteLine( item.ChildItemList.First().Parent != null); // False
        Console.WriteLine( item.ChildItemDict.Values.First().Parent != null); // False
    }
}