Potential double spend attempts

[buckyball]

When a peer receives a transaction that uses the same inputs as a transaction that is already in the mempool it will not put the new transaction into the mempool.

However, will the peer:

a) Keep a copy of the transaction so that it can be retrieved through the getrawtransaction RPC call?
b) Notify on the ZMQ interface that it received both the second transaction as well as the first?

Thanks!