Or the author can remove himself to another room, seeing how another baby is on the way.
As you said yourself, there might only be one double room in the property. If the houses have two double rooms, why should the author be the one to move when he is not the one creating the noise? If you're suggesting he moves out to sleep in a single room; again, why should the couple not making the noise be the ones who have to sleep separately? The parents could take it in turns to sleep in a single room alongside the cot.
Or get earplugs as many people suggested.
Not a long-term solution. Aside from the discomfort, they're a risk if there's a fire in the house as the smoke alarm might not wake you.