how did u manage took ticket n cheaper like this?  how long will the duration of flight?
i had only book dosmestic nvr international...  planning one from kl-tokyo

Used Vietnam Airlines during Feb. Any question you'd like to ask?

How long is your transit? If its only 1 hour, I'll suggest not to go anywhere. Just get off, pass through immigration, walk nearby/ stretch a little and perhaps a short toilet break then queue up again for immigration to get back in. The troublesome thing is to get off, pass through immigration then pass through immigration and get on again.

If your transit is 2 hours long, consider resting at nearby lounge. Friends and I did that for our transit to Nagoya. Paid a small fee to access a lounge that has WIFI, plug point to charge phone, drinks, pillow and comfortable coach to nap.

And oh, bring some Vietnamese Duong or USD just in case you decided to spend at the airport, or if there's an urgent need to buy something for your child.

Good to hear its a stopover at HCM. I have no problem with the airport, everything was fine. The only unpleasant experience was at Hanoi airport on our transit back.

you can read my review on VN experience  here
overall, good for its price (got it cheap @ peak season)

no need to recheck in baggage. it's done point-point, meaning eg: KL-Tokyo.
nothing is needed, just go try a small immigration bag scanner and you are back at the departure hall
yes 30kg( do check if it has changed)