Or they won't even notice. OR they will want to sleep on or near the baby to claim it as new territory. That bit you might want to watch out for initially.
I was going to mention that. We has cats when my oldest were born and the two biggest issues we had was them wanting to sleep on the baby or getting overly affectionate/acting up when the baby was getting more attention than them. Took 'em a couple of weeks but they soon got bored with it all and went back to their old routine.