I see that you uploaded it from your phone. Did you take a Pic of that Pic with your phone? Not very good Resolution (Pixely). If you could scan that at a Higher Resolution or take a Pic at a Higher Resolution we could give you something worthy of framing.
I thought I would have a go with this. In addition to setting white balance points and doing a bit of levels and curves adjustments I also straightened the image a bit and cropped in to what I think is a more pleasing framing. I also used a high pass filter to sharpen slightly.