H1B extension, dependent status?

Hi ,

My H1B visa is going to expire by Sept30 and my company has processed Extension and current status is LCA filed and waiting for receipt number.

My question is like , whether i can bring my family before Sept30 (they have H4 visa with same end date)? will there be a problem after visa expiry, as my extension will still be in approval process and i may get it approved only by november or december ?