Dandruff in 3 Years Old Kid

Anyone can have dandruff at any age.
In babies and toddlers they call it cradle cap but it's just another term for seborrheic dermatitis.

You could try using a dandruff shampoo but be careful as it will sting if it gets in her eyes - so rinse carefully.
You could dissolve an uncoated aspirin (a few drops of water will cause it to break up) and then mix that in with the little bit of baby shampoo you use to wash her hair.
The salicylic acid (aspirin) added to any shampoo is like making your own dandruff shampoo and helps keep the flakes away.
If you think the cause might be fungal, get a little Tinactin cream in a tube and rub a little into her scalp and see if that makes any difference.

http://health.howstuffworks.com/skin-care/problems/baby/5...

My boys both get it from time to time and have since they were small. I just use Head and Shoulders for 2 or 3 washes and it is taken care of. Follow the diresctions on the bottle, it has to stay on the hair for 5 minutes.

If it is just one small patch then it doesn't sound like dandruff to me. Maybe Eczema? I would show it to your doctor. But I really wouldn't use a dandruff shampoo on a 3 year old without talking to the doctor first--they have terrible terrible chemicals in them. If it is eczema you might be better off rubbing lotion into it or possibly a hydrocortisone cream. But check with the doctor first!

It could be dandruff, but not rinsing shampoo and/or conditioner out completely can cause this as well, when she's bathed is her hair washed with shampoo, not soap, and rinsed with clean, not soapy water? I would have her doctor take a look at it, has she had her 3 year checkup? My oldest granddaughter had the same problem and my DIL's friends told her it was cradle cap as an infant, to apply baby oil and it would be fine. Well, it wasn't and when she finally brought it to the ped's attention she found it to be something else. At the very least call your pharmacist and run it by him or her to see what advice you get.

make sure its not product build up. My boys had this and it was fixed with a clarifiying shamoo and a good scalp massage.

My daughter gets it if she doesn't rinse her shampoo out enough. Maybe it's a shampoo or soap that is irritating her.