Sukie - you are not idiotic - you have my sympathy. I might as well get called idiotic and flamed too.
I had a neighbour similar to yours, but there were 2 children (age 3 and 5)and also a dog. Difficult for me to move, as I owned the house, she rented.
The noise was awful. Dog barking at all hours, inside the house and in the back yard. The children were in the main bedroom right next to mine and they would be shouting and screaming at 1am in the morning. After about an hour, she would come in and start shouting and screaming at the children. She would also tell them to shut the f@&k up and call them shits, wankers and bas@/&ds. We used to get the tv blaring all weekend and the kids running round the house shouting and banging on the walls and slamming doors.
It drove me bloody mad and actually got me very stressed. I was regularly knackered in work and never got a lie-in on a weekend due to the noise from her children.
I did approach her nicely to start with and politely explained the impact of the noise from her house. She wasn't arsed. Just said her children were entitled to have fun! I did lose it one day and went round and told her to shut her f@&ing children up. This was after months of constant noise.
In the end, I complained to environment health and her landlord. After showing her landlord (social housing) a diary I kept for a month, they actually moved her. She took great delight in telling the other neighbours that the 'snotty cow' next door got her thrown out!
People do need to be considerate of the noise their toddlers/children make. I was very conscious and still am where my DS is concerned that we don't annoy our neighbours, as they are lovely. We had a few of his friends round last Sunday and they did make a fair bit of noise, so they were asked to keep it down. I did go round to my neighbours in the afternoon and apologised if they had disturbed her. Luckily she had been out, so didn't hear them.
Suzie, I am sure you will be a very considerate neighbour when your little one arrives.