Do people actually pay to have portraits and kids pictures taken, you don't see many studios on the High st. anymore, the quality of camera phone pictures (as the OP's wife has found) is very good now, and you can keep pressing the button until you get a good shot. So long as you have a vague eye for composition and lighting you're good to go.

Frankly most family group type portraits you see hanging on peoples walls look pretty naff to me!