Hello, my sister just rang and has asked me to take a picture of her family (only 3 of them) so they can frame them and send them as xmas presents as they don't have much money.

For some reason I said yes, now I am sure I can do something reasonable, but my only issue is lighting, I don't have any I always shoot natural light I have been playing with a light bulb but that also will not work. So what issues will I face what should I be careful of and how can I bodge this together to make it work