Drop box documents for H4 extension of kid

I am planning to travel India for family emergency along with my child. I will have to go for my H1 visa stamping interview. But my child is eligible for dropbox to do H4 extension based on my spouse’s approved H1 extension. Does the child’s application need copies of unexpired visas of both parents OR copy of my spouse approved I797(H1 extension) is enough?

As per current rule, they require both parent’s visa copies.