We live in a terrace. On one side is a single guy, we very rarely hear anything from his side.
On the other side we have fairly new neighbours, a slightly older couple, but I think they have small children staying occasionally (maybe grandchildren or nieces/nephews). On that side, their stairs back onto ours.
This morning our toddler was awoken (not that early, about 15 minutes ago, but still too early as she normally sleeps in till 8 or 9) by what sounded like someone running up and down the stairs repeatedly. I should point out that DD's room is not against the adjoining wall. Prior to the stairs I heard something that sounded like DD shouting, but when I checked the monitor it wasn't her. So it must have been noise from next door (but loud enough to make me think it was coming from our house).
It's not the first time she's been woken by noises from over there, last time it happened she was napping and it was the middle of the day. Bear in mind we make all sorts of noise while she's asleep, we don't tiptoe around, but this was a door slamming or similar so very sudden and made us jump too.
I know it's not their fault the soundproofing isn't great. But the previous neighbours had absolutely no idea when our toddler was born (they knew I was pregnant so would have been expecting it) as they couldn't hear her through the walls.
I don't expect them to be especially quiet all day just in case she's napping. But should I speak to them and make them aware just how much noise carries in the properties? And how certain noises carry more than others? (Perhaps I could go and apologise in case DD has been disturbing them, she's teething and well, you know how noise carries in these terraces, hint hint)