Sheamoisture is a product line that is sold at Walgreens. It is organic and gets rave reviews from many curly heads and parents of curly heads. They have a kids line but I have never tried it. It costs about 10$ a bottle.
I see that you live in Netherlands, so you'll have to order these products recs from the curlmart. What type of stores are in the Netherlands? Is there a Surinamese and/or black community near where you live? For a detangler you can mix conditioner w/ water and evoo & spritz and then comb her hair?