Upvote:4
It's been a while since this question is asked but let this answer help someone out who is having the same question.
If you have a general ticket, you might need to pay the difference between general ticket fare from reserved half ticket fare. Let me also remind you that it is not desirable(to be read as not legal) to travel without a proper ticket.
For a child, 5 to 12 years, half of the adult fare is charged even if a berth is not required.
If berth is required, the full adult fare is to be paid.
Source - Press Information Bureau, Government of India
Press release link - http://pib.nic.in/newsite/PrintRelease.aspx?relid=138458