Brief Answer:
As long as she is active, no need to worry.

Detailed Answer:
Hello sir,
. Actually 8 kg for 1 year 6 months is low. The following are indicators of good health in a child :
1)child is active
2)child feels hungry
3) child plays well
4) is not cranky all the time.
As your child fulfills the above criteria, you don't need to worry.
The following are few tips to increase your child's weight :
1)child should have food every 2 hrs
2)carbohydrates, fats can be given liberally.
3)eating an egg daily would take care of protein.
4)if she Can eat non veg food, you can give it weekly twice.
5) foods fortified with iron, calcium are to be given frequently.
6) physical activity like playing outside is to be encouraged rather than indoor games.
Weight is not a matter of concern as long as she stays active. Slowly the weight will be put up.
Hope I have answered your question. Please let me know if you need further assistance. Thank you.
Take care.

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