You have to mix tinctures with freshly pressed apple juice, or with maple syrup, if you want kids to swallow it.
Make sure you keep you kid away from Sugar and from any other concentrated sweetener (maple syrup to mix with tincture is ok).
You can also restrict bread consumption, and any pasteurized juice or any other pasteurized drink.
Learn how to make home made yoghurt, it can be that your child has some intestinal infection caused by the lack of good bacteria. You can find recipe for home made yoghurt on the web.
You should also try to get Grapefruit seed extract, and you can add it into juice, it is a very potent natural antibiotic.
The brand that I know works is called "Cintamani". www.cintamani.com
I have no experience with other brands, but I know that some other brands are far from the effectiveness of Cintamani.
In toddlers, you can give Yoghurt Enema by using an oil lubricated small glass pipette, like one used for eye or ear drops.
You fill it up with yoghurt, and you squeeze it into the rectum, after child has had BM.
Even better then yoghurt is fecal flora replacement.
You take feces from a healthy baby, dilute it in water, and squeeze it into rectum with a pipette.