Thank you for your query on Healthcare Magic.
in this age group is due to lack of dietary fiber
in the routine daily diet.
Give dietary fiber rich diet like vegetables, leafy vegetables, and fruits in daily diet.
Give her plenty of water and oral fluids.
Don't give excessive milk.
If she is having hard stools at present she can be given oral stool softeners like lactulose
in prescribed dose for 3 to 5 days.
and underlying organic problems to be ruled by appropriate investigations out if the problem persists even after doing the above measures.
Hope I have answered your query.