Can anyone help or advise please? We are having second babe in April and first one will be 17 months only. We currently use Tomy baby monitor as his door is closed once sleeping. Planning to putnew baby in separate room but unsure as to whether we need to buy another monitor (but if we do will there be interference between the 2 monitors?) or can we get a spare 'handset' so to speak in order to heae both babies should they wake. Does this make sense and can anyone help? Thanks