H4 Visa Interview waiver program help need

[Hima81]

I am in India and have a kid of 4yrs old . We had valid US H4 stamped visas untill December 1st 2017 . My husband is on H1 and is in US.
Now am going to renew our visas through interview waiver (Dropbox), for that can I submit our both passports at same time ?or I need to get my visa stamping first and then go for her visa?

Please clarify. Thanks