Have you seen the room yet ? If you could stick to half body shots , as long as they have a plain(ish) wall, pose them four feet in front, use a wide aperture & blow the background out. Much easier than having to setup backgrounds & tbh I am not a fan of the mottled coloured backgrounds anyway. Reminds me of school photos
Example :-
If you go the full length route, especially white, then you really need more than 2 lights, which makes life even more complicated.
Some of the best portrait shot's I've seen are usually around weddings. 99% of these are taken in situ, with no special backgrounds. If you can think like these wedding photographers, when they are shooting the bride getting ready at home etc, then why not adapt that style to your kids portraits.
I recently viewed a DVD of an australian portrait photographer who had 3 simple steps to some stunning portraits (albeit mainly outdoors)
1. Find an interesting background
2. Finding an interesting foreground
3. Ensure the lighting is correct
By placing the person between 1 & 2, if you get 2 points right you get a good photo. If you get all 3 right, you get a WOW photo.
Taking this in a house, for #1 you could have a fireplace, a door frame, a diagonal of a staircase. For #2 you could have them crouching behind a stool, or chair , rest arms on top. For #3 , if lucky you can deal with just natural light from a large window, use flash or studio lighting.
Add to this if you convert to mono, the potentially distracting mixture of background colours can become a texture that compliments the photo , you have lots of options to play with.
Examples :-
Just my 2p worth
