MinnieMountain, I'm so sorry. This IS hard.
I lost my beloved mum in May. I can barely stand to type the words out actually. I hate it so. But I can say this...do not be afraid to cry in front of your child. That is normal. That shows your child that you are grieving, that you feel loss after a loved one goes, and that it is normal and ok to cry. Talk to your child. I had to tell my three, and it was so heart wrenching. We had lost our beloved family dog only weeks before (they had grown up with her), and so this felt so cruel.
I can only lend you my empathy and say to keep talking with your mum, and allow yourself that time. And it is a lot of time. Nothing will ever go back to normal, you are on a different path now. That's how I feel it anyway. I find that expanding out to talk to the RIGHT people and then retreating in to just be, are the most natural and helpful ways to process this dreadful heartbreak.
I read through a lot of this thread the other day when I was really struggling (my mum was everything to me, and we shared a lot of trauma together and were the best of friends, as well as her being the best mum), and my heart swelled at feeling every one of these losses.
Be kind and gentle with yourself, this is so very early. And it is never 'over', so push away any pressures of when it is expected that you will be done grieving.
Sending loving hugs x