Taken last month - she's 11 months now.
Welcome! We are next door in Kent with a 6 month old called Ellie. I think there are a few Basenjis in London.
We also have an 11 month old and I have had to spend a lot of time training my children to recognise when she doesn't want affection e.g. lip smacking, yawning and looking away. With consistent reminding they now understand and sometimes have to remind me They are older though (8 and 14) so easier to train.
As already suggested a separate Basenji sleeping area that is out of bounds to your 3 year old would be helpful. We use an open crate with a blanket over the top and none of us approach it when she does in there for peace and quiet.
How old is your other child? Can they help to remind your 3 year old?
Ellie (9 months) got a surprise whilst out on a walk!
My 11 month old went into the vet alone last month and did not consent to being examined. The vet said she was "a bit snappy" and that they tried to muzzle her, but that she wouldn't accept that either, so they used a rolled up towel around her neck, which they said calmed her and prevented her from biting..She didn't seem concerned about her snapping and appreciated that she didn't know them and was alone.
I had to take her again today (to a different branch) and due to that memory she was very reluctant to go in, but thankfully due to Covid restrictions being lifted here in the UK I was allowed in with her. The vet asked me to put one hand under her chin/jaw and to hold her collar with the other while she was examined. There was a small growl when the thermometer went into her back passage (can't blame her!) but me gently restraining her in that way whilst giving lots of verbal praise worked really well.
She also doesn't like strangers approaching her overhead, so I ask people to hold their hand out and let her approach them before scratching her under the chin, pointing out her hackles and that she is nervous. This approach has allowed her to say hello to multiple people, which she really enjoys.
It might be worth shopping around for a different vet who is more patient and willing to think creatively to help your dog tolerate bring examined. Also hopefully it won't be long before you are able to go in with her.
Just went out for a walk and the man that she growled at last week came out of his house with some dog biscuits for her. He put a couple on his front wall, which she ate and then came out and squatted down and she took some more from his hand. I thought that was nice of him to proactively try and help.
It might be also worth consulting with your vet to make sure there's nothing medical going on that would cause this change in behaviour in her sleep.
Our Basenji loves tug of war, but we don't go too far and mostly let her win!