Brief Answer:
Monitor the temperature,give antipyratic and observe

Detailed Answer:
Hello

Thanks for asking the query

The most common cause of fever in this age is some viral respiratory of intestinal infection.
I would suggest you to give him antipyratic like paracetamol.The dose of paracetamol is 10-15 mg/kg/dose and it can be given three to four times a day.
The average weight of 12 months old child is about 8-10 kg.So the dose of paracetamol(calpol/crocin) would be 5ml(each 5 ml contains 20 mg).
Monitor the temperature and observe for appearance of any new symptoms like cough,cold or loose stool.

I hope this helps.
Please let me know if you have any more query.
Regards

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Brief Answer:
Appetite will improve within few days

Detailed Answer:
Sorry for delayed reply

In any acute illness there is decrease in appetite.
It improves as general condition gets better.Try to give plenty of fluids to avoid dehydration.
I won't get worried if baby is active and passing urine well.
Encourage him for feeds.You may give food of his choice.
I suggest you to keep patience continue trying to feed him.

Thanks and regards

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