✔ 最佳答案
You need to buy an air ticket for your baby even though it's only 6 months old. The price is 1/10 of original price. But the tax is the same as adult and you need to pay tax for it. When your baby reaches the age of 2, then he/ she needs to buy a ticket with full fare. As for hotel, as long as the baby sleeps with you, you do not need to pay extra for it.
Japan is a modern city. There're lots of facilities in shopping malls or public places for babies such as milk feeding room in department store or napkin-changing room in female lavatory. You can buy milk powder or other daily necessities easily as well. So it's not a big problem.
Have a nice trip with your baby!