Thank you for all your support - DH has been letting me think I'm just a paranoid fool and I'm over reacting. TBH I do have a tenancy to over react to things so to hear others saying I'm not being unreasonable reassures me.
PIL are lovely people, I can't see them getting angry about saying he can't drive DD but I can seeing them being hurt about it. I can also see that it can cause logistical issues for them as when they have their other grandkids in the holidays they like to take them all out. Lately they even asked about FIL getting insured on our 7 seater so they can take them all out. Not a chance!!
I think DH needs to speak to MIL first, she may have noticed the decline in his driving too and if she has then it would come better from her.
Regarding the accident, he wasn't prosecuted, probably because nobody else was involved and they weren't really sure what caused it. He was driving down the motorway and somehow ended up crashed in to the wall of a motorway bridge, he thinks he must have been clipped by a lorry but there was no evidence of that.
According to DH as he was driving for a living at the time he was made to undergo some kind of check to make sure he was fit to drive, so apparently that means he's fine. But I'm not sure if he is just assuming that or knows that for a fact, or maybe he failed and that's why he retired soon after?
I am greatly concerned about his health. He has a terrible terrible cough and you can here is chest rattle with every breathe he takes, I asked DH about it and he said it's just some bronchus problem he's had for years. But I strongly suspect that it's COPD which I watched my Grandma die a horrible death from.
I don't even know if he has been properly checked out and receiving medical treatment for it. Of course he smokes which is another issue. Since he's retired so spending more time at home the house stinks of smoke and so does the car.
I need to look for other childcare don't I? But I know it will break MIL's heart for her to stop looking after DD, she lives for her DGC and is a fantastic Grandma 