If you search for Birdbrook in the forum search there are lots of posts with comments about it ..... Here is a post (not about Birdbrook Rd but does show it) and I think your Nan's house is probably in the aerial view. See Goodway Rd running down from Kingstanding Rd
click pic twice and it enlarges it or save it
and if you haven't already seen it, here is a modern view of your Nan's house ... red car.
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