Swap Model Via Button

I wanted to swap model by pressing a button and here is my codes however when I press the button my existing model just disappears and the one that is supposed to replace it doesnt show what could be the problem?

public class ModelSwap : MonoBehaviour{

    public TrackableBehaviour theTrackable;    private bool mSwapModel = false;

    // Use this for initialization    void Start()    {        if (theTrackable == null)        {            Debug.Log("Trackabale not set");        }    }

    // Update is called once per frame    void Update()    {        if (mSwapModel && theTrackable != null)        {            SwapModel();            mSwapModel = false;        }    }    void OnGUI()    {        if (GUI.Button(new Rect(50, 50, 120, 40), "Swap"))        {            mSwapModel = true;        }    }

    private void SwapModel()    {        GameObject trackableGameObject = theTrackable.gameObject;

        for (int i = 0; i < trackableGameObject.transform.childCount; i++)        {            Transform child = trackableGameObject.transform.GetChild(i);            child.gameObject.SetActive(false);        }

        GameObject Baker_house = GameObject.Find("Baker_house");

        Baker_house.transform.parent = theTrackable.transform;        Baker_house.transform.localPosition = new Vector3(0, 0.2f, 0);        Baker_house.transform.localRotation = Quaternion.identity;        Baker_house.transform.localScale = new Vector3(0.1f, 0.1f, 0.1f);

        Baker_house.SetActive(true);    }}