In Book 20 Why can't Odysseus sleep? Why can't Penelope sleep? Who does penelope pray too? Who does Odysseus pray too? and what is significant this chain of events

It's the night before Odysseus gets to slaughter lots of men (suitors perhaps!) ,he can't sleep. Besides everybody seems to be having sex but him. Penelope dreams that Odysseus comes back. I believe they prayed to Jove and Minerva.I think this pretty much means the end of the suitors.