That should totally be doable. Partly look at the pairs - two oldest, next two and then the baby is group three. Do the 4 of them pair up to have a friend or just fight amongst themselves for control of the group - that makes a difference in how much time you need to intervene. If they are pretty much independent in play then that leaves you to help the youngest join in but they will be walking, starting to talk, feed themselves, etc. so not far behind. I say go for it.