Gamemanger.cs

private PhotonView PV;

    private void Start()
    {
        PV = GetComponent<PhotonView>(); //create inital PhotonView object to reference later
    }

    void Update()
    {


        if (time <= 0)
        {
            ChangeTurn();
            time = 3;
        }
        else
        {
            time -= Time.deltaTime;
        }

        if (players.Count > numberOfPlayers) //if a new player joins give them a colour
        {
            Vector3 init = new Vector3(0, 0, 3);
            numberOfPlayers = players.Count;

            GameObject playerColour = colours[0];

            players[players.Count - 1].transform.position = init;

            colours.RemoveAt(0);

            PV.RPC("RPCSyncColours", RpcTarget.Others, playerColour.GetComponent<PhotonView>().ViewID); //pass ID

            //object[] content = new object[] { playerColour };

            //PhotonNetwork.RaiseEvent(evCode, content, RaiseEventOptions.Default, SendOptions.SendUnreliable);

            print("set child");
        }

    }

[PunRPC]
    void RPCSyncColours(int ID)
    {
        print("Changed colours");
    }


player.cs

 private void Update()
    {
        if (photonView.IsMine)
        {
            if (Input.GetKeyDown("space") && isTurn)
            {
                print("User pressed space!");
            }
        }


    }

 [PunRPC]
    public void RPCSyncColours(int ID)
    {
        print("added colour " + ID);

        PhotonView colour = PhotonView.Find(ID);

        colour.gameObject.transform.parent = this.gameObject.transform; //set colour to this object as child

    }