SIL is looking to buy the house which backs onto ours.
We don't live very far from her now - maybe 2 miles - and she is nice but I still feel weird about her buying the house. It will mean that they can see into our garden from their upstairs windows and that we would always be able to see/hear each other when out in the garden.
We get on just fine at the moment but we don't socialise all the time - just the usual family events. She is already joking about putting in a gate so that her DS's can come and go as they please!