L.G.
I personally think that a shower for a second baby is not necessary, and definitely not appropriate to hint. The only exception might be if she did not receive all the necessities for her first for some reason or it's several years later, which in her case it's not. If she is having a girl, maybe some close friends would want to bring clothes, but a lot of friends do that anyway without a gathering. Don't feel guilty if you don't host anything!