go first class. your benefit, the child's benefit and the other passengers. i just arrived home on a flight with a baby nearby my seating. the poor family. the baby was having an extremely bad day. crying like a baby, as they say. everyone was so annoyed on the plane. i felt bad for everyone. especially the family. it was a night flight, so people wanted to sleep. no chance of that happening.
hopefully, your child will make things alittle easy on you. good luck and safe travelling.