How to get specific data of a node in Firebase, or the specific Data of a Java Object

I have these nodes, each of these nodes contains data, They are structured in this way

In the "MainActivity" I have a map, on the map there are three markers

Each one of these markers contains data which are so

I rescue the data from Firebase in this way:

  FirebaseUtils.getPostRef().orderByKey().addChildEventListener(new ChildEventListener() {
                    @Override
                    public void onChildAdded(final DataSnapshot dataSnapshot, String s) {
                        // posicion
                        latitud = dataSnapshot.getValue(Post.class).getLatitud();
                        longitud = dataSnapshot.getValue(Post.class).getLongitud();

                        // datos
                        titulo = dataSnapshot.getValue(Post.class).getTitulo();
                        costo = dataSnapshot.getValue(Post.class).getCosto();
                        mes = dataSnapshot.getValue(Post.class).getMes();
                        numeroDia = dataSnapshot.getValue(Post.class).getDia();
                        organizadoPor = dataSnapshot.getValue(Post.class).getOrganizadoPor();
                        descripcion = dataSnapshot.getValue(Post.class).getDescripicion();
                        hora = dataSnapshot.getValue(Post.class).getHora();
                        minutos = dataSnapshot.getValue(Post.class).getMinutos();
                        id = dataSnapshot.getValue(Post.class).getId();


                        final ArrayList<Post> pp = new ArrayList<Post>();

                        // marker
                        BitmapDescriptor bm = BitmapDescriptorFactory.fromResource(R.mipmap.m5);
                        LatLng latLng1 = new LatLng(latitud, longitud);
                        mMarker = new MarkerOptions().position(latLng1).title(titulo).snippet(costo).icon(bm);



                         mp.add(mMap.addMarker(mMarker));

                        mPost.setTitulo(titulo);

                        final Marker mk656 = mMap.addMarker(new MarkerOptions().position(latLng1).title(titulo).snippet(costo).icon(bm));
                        mk656.setTag(mPost);
                        mp.add(mk656);
    }

All that method puts markers on the map, Now the problem is:

By clicking on a marker I need that specific data For example marker 1 has Title "HELLO"

I need to click on that information "HELLO" is rescued with another activity

Try this with my model class      Post mPost = new Post ();          Intent intent = new Intent (MainAcivity.this, AnotherActicity.class);          intent.putExtra ("post", mPost);          startActivity (intent);

and this in the other activity:

    Intent intentI = getIntent();
    mPost = (Post) intentI.getSerializableExtra("post");
    initPantallaPrincipal();

The data is received successfully, but the data of the last added marker is received for example:

I add a marker A with Title A

and I click on the B marker with title B

in the "AnotherActivity" where I rescue the data I get the data of the marker A bone the last addition and I need the data of the specific marker