Anniversary Caricature - Sketch 1

I have a caricature commissioned for a 30th wedding anniversary gift, and this is the first sketch so far.  The photo I'm using shows the couple in a pose similar to this, but I've changed a few details to add interest.  I'll do another sketch tomorrow, adding in more details requested for the background and refining the drawing. Then I'll need to decide  between using watercolor or chalk pastels for the coloring.  I have done watercolor before, but I think the chalk would have a softer effect more suitable to the couple and the occasion.  I'll probably give both a try and then decide.  Stay tuned.