About American immigrants. I-730 gets a visa, can domestic families go in batches?

After the interview is successful, if you are notified to pick up your bag after half a year's review period, you can probably go together.

If you come down quickly, it is no problem to walk separately. You can stay in China for half a year after you get the parcel. Judging from the time you mentioned, your brother will not delay his studies.