DD aged 9 has thick, wavy, frizzy hair - she hates it. She loves it when she gets it cut and it's beautifully straight and tame, but I can't get the same look at home. She doesn't mind it curly if it's not frizzy, but I don't know what to use without leaving it lank and greasy looking. Am trying argan oil but it's not really doing much. Any suggestions?