Visitor visa expiring after passport expiry date


My mom n dad’s visitor visa expires in Oct’22 but passport expires in Apr’22, so after renewing the passport can they carry old passport along with new passport to travel as the stamping on old passport is still valid? after landing in US can i apply for their extension of stay?

Yes, this is exactly what they will need to do.

They may get I-94 for up to 6 months from the CBP at port of entry when they enter however you can request an extension beyond 6 months provided there is a valid reason such as unable to travel due to medical reason etc.