As a Cosmetologist here is my advice.
1. BEFORE you get the Hair wet for shampooing Brush it very well. Then DO NOT pile the hair on top of head to shampoo.
Get fingers into the hair and cleanse the scalp then work down to the the ends. By taking the hair in your hand and rubbing together to cause FRICTION, that and the soap clean the hair.
Rinse and Repeat even if you do not think you need to shampoo twice you really do. The first takes the dirt and grime off the surface the next one actually cleanses.
a GOOD SHAMPOO you should only need the size of a dime of shampoo. (First week using a good product--size of a nickle to quarter---this eats the wax that is in most cheap shampoos, work to reduce to size of a pea to a dime of shampoo)
2. NEXT use the conditioner, start at the Bottom of the hair shaft and work upward. Most of it is needed on the ends not the scalp. WHILE STILL IN THE TUB--Then take a detangler comb or a Large wide tooth comb and start while the conditioner is still in the hair and she is in the tub! THEN RINSE BY HAVING HER SIT UP AND PUT HER HEAD BACK. Use a wash cloth for eyes.
DO NOT RINSE AND RINSE. KEEP JUST A LITTLE BIT IN THE HAIR... NOT ENOUGH TO MAKE IT LOOK DIRTY BUT ENOUGH TO GET A COMB THROUGH IT.(USE YOUR JUDGMENT AND TRAIL AND ERROR)
Next use a detangle spray if the privious was not enough to stop the real bad pain.
Take SMALL sections of hair and comb from the bottom up.
3. Let your daughter know that she NEEDS to toughen up her head some and this will help her later in life. (I still have baby fine thin hair but I have done this as well as toughened up my own head to make it work!) Remember the quote mom used to tell "We must endure the Pain to be beautiful!"
Finally, make sure you are using a good shampoo, talk to your stylist for her recommendations. Every Salon has a few lines to choose from and all price ranges. A good Salon formula will last longer and be LESS EXPENSIVE in the long run.
TRY THIS- GET A NEW BOTTLE OF YOUR CHEAP BRAND, MARK IT ON THE CALENDAR TO SEE HOW LONG IT TAKES YOU TO USE IT UP. THEN GO BUY A SALON PRODUCT-- MARK THAT ON THE CALENDAR TO SEE HOW LONG IT TAKE YOU TO USE IT UP. MOST CHEAPER BRANDS HAVE THE WAX. THUS, COATING THE HAIR. It usually takes a quarter or more for a good lather per shampoo.
The salon product as stated above--takes about a week-to two weeks to remove the waxy build up from the hair thus taking a size of a nickle. After that a PEA to a DIME size is all you should NEED!
After a baby is a year old they no longer should be using baby shampoo. This is why so many kids have cradle cap at 7-9 years old. It is for BABIES, before the glands start to develop. Always, brush the scalp BEFORE shampooing the help remove the dirt and grime from the scalp and hair shaft.
If you have a problem with this use a TEA TREE shampoo to help heal the scalp and hair.
ALWAYS SMELL YOUR CHILDS HEAD, to see if they are clean enough after shampooing. THIS WILL TELL YOU IF YOUR PRODUCT IS WORKING! If they still smell dirty-- THEY ARE---CHANGE PRODUCTS. What works for one in the house does NOT always work for everyone.
CHECK THE KIDS WHEN THEY FIRST START TO SHOWER THEMSELVES AS WELL. BIGGEST PROBLEM-- NOT RINSING THE SOAP OUT OF HAIR. CAUSES A SCALP BUILD UP AND CAN CAUSE SOARS ON THE SCALP WHICH CAN LEAD TO OTHER PROBLEMS AS WELL.
I hope this helps, I have added the other tips as well to help you with the older child too.
Best of luck