Urgh, just lost a long post, so sorry if this is a bit blunt!
Anna so sorry to hear about your Mum.
My Dad went through cancer treatment in the run up to my wedding (and even had a round the night before) and it really helped him to have a distraction and something to look forward to, so you and your baby will be a huge comfort.
I don't want this to give any false hope, but it might be worth checking with your Mum's doctor whether your baby's cord blood stem cells might be useful in your Mum's treatment?
Mar sorry you're having a rough time, take care of yourself. 
Those moving house and having building works done, wishing you a very smooth process! We still have no door handles after "finishing" our works last October. I'm considering it advance baby-proofing (with the unfortunate side-effect of also husband-proofing when I had to come home from work early to let him out of the bedroom)
RE weight gain, I stopped measuring when I hit 25% gain on my pre-pregnancy weight
I've just sneakily checked and actually it's barely gone up since, and I've heard that its normal not to put much on in third trimester, I suppose baby runs out of room and it's more development than growing now.
When is everyone starting mat leave (in terms of weeks gestation)? I was due to stop at 36+3, but my husband has just found out our due date is 1 week too early for him to get 3 months paternity leave. We're absolutely gutted, he was really looking forward to looking after baby himself. So now think I'm going to wait as long as possible so he can afford to take some unpaid leave instead.
And parting advice - don't forget your pelvic floor just had my first coughing accident 
35+2