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Originally Posted by
jimallen2011
I'm looking to book award reservation from US to Hong Kong for the summer (August) on AA miles; we only have enough miles to purchase 2 business and 1 coach tickets.
If I book coach class for my 7 years old and business class for spouse and myself, would my kid be allowed to stay with her mother during the flight? My 7 years old is short and small.

Will we able to get free upgrade for my kid in the spot if there are non-booked business seat?
You need more miles or you should buy a discount business class seat for one of your party of three and then redeem miles for the other two business class seats. Apply for more credit cards and satisfy the sign-up bonuses if you're short miles.
No airline is going to permit you to book a 7-year old in an economy seat unaccompanied and then permit that 7-year old to hang out with their parents in business class. That ain't how the world works. It's never worked that way.
Originally Posted by
jimallen2011
I could also book coach class for myself and business class for spouse and my kid. But I am afraid the odd for me to stay with them is slim.
You could do that, but then you'd be sitting in economy class. Yuck.
Originally Posted by
jimallen2011
What else? Any hint about making the above arrangement to work better? Thanks in advance!
You need more miles or you need to spend some money. If you want to sit in a premium cabin, then either leave your children home or get them premium cabin seats with miles or actual cold hard cash.