In the late 1990's, my wife and I had the sure fire way to avoid red stains in the dining room. This was to install wine colored carpet in said room. As with any color other than neutral, it made the room look very dated. Fast forward about ten years and we participated in Big Brothers, Big Sisters. We had a very nice young man stay over (he was 10 at the time) and he spilled grape soda on our nearly white carpeting in the living room. We were renting at the time (sold our house in 2000, long story) and these stains are impossible to get out with carpet cleaners. Even people who do this for a living will use a two part treatment to make the stain invisible and it is expensive. More often than the not, the carpet will have to replaced or the stained part cut out and a new section installed. Either the carpet will never look right, or you spend beau coups bucks on replacing it; not to mention moving all your stuff around to get it done.
I can do a lot of things, but carpeting is not one of them. When my wife spilled a glass full of fruit punch in our dining room, I was livid. We don't even buy colored juice drinks for this very reason, but Subway so lovingly supplies this stuff to unwitting parents daily. If it gets on anything lighter than it is, you're going to have a potentially expensive headache. Domestic issues aside, there is a solution short of replacing your carpeting or furniture, much less screaming at your spouse or children. Scold them if you must, but I would try this first.
As with anything I suggest, there is the potential for personal injury or property damage. You could follow the directions to the letter and still mess something up. I have no control over your work or any other issues involved. Do this at your own risk.
You'll need an iron, some white towels or cloth diapers, a faucet, and some Dawn dish washing soap. Not the foam, but the original, blue Dawn. Accept no store brands or substitutes. Get your cloth diaper or towel wet and then add the Dawn to it. Work it in the cloth without wringing it too much. Then fold it in half and lay it over the stain. Set your iron to the highest setting and lay it on the cloth until the cloth starts to steam. After a minute, lift up the iron and check the cloth. The stain should be transferring from the carpet to the cloth. This is where intuition comes in. Once the cloth can't accept more of the stain, turn it over and see how much more of the stain you can bring up. Use the cloths and iron, moving them around until the stain is no longer visible on the surface you're cleaning up. Take your time and don't let the cloth get dry or place a hot iron on the carpet or you will be replacing it. If you do it right, you've saved a lot of money and maybe even your relationship. Maranatha!