The checklist that I posted is for reference only. Qty of each item is very depend on your BB situation.
e.g. I took my son to Tokyo four mths ago. He is almost 2.5yrs old. I didn't need to bring 吹氣盆, he took shower with my hubby and he really enjoyed. He drinks (by baby bottle) milk 3~4 times a day. Thus, I needed to bring 4 bottles (3 for use, 1 for spare) to ensure I only needed to clean bottle once a day (travel, no time ma!)
Regarding no. of diapers, it depends on where you go and whether your BB has quitted to use diapers during day time. My son doesn't need diapers in daytime. I brought 12 pcs for 6 days but still not enough because my BB was 水土不服 and I needed to buy a pack on the 4th day. Luckily, it's not hard to find and buy diapers in Jpn.
Besides, I only brought 4 favourite toys of my son and bought some new in Toyko. Of course, he was happy to play new toys during the journey la
Finally, please be reminded to bring around 1~1.5L "HK" water with you and mix with "local" water time by time to avoid 水土不服. My hubby let my BB drank a small cup of hot chocolate bought from airport cafe once we arrived. Then, my BB 就出事 la! :-(