You are understandably shocked by your father's unexpected death - presumably his doctors were too, as it sounds as if he had not been warned he might not survive.
Give yourself time to be sad and mourn your father, and I am very sorry for you loss.
Sit down with your husband and discuss what you and he want to do this Christmas and have the Christmas you want.
Leave your mum and sister to do what they want, but mention to your mum that you cannot face decorating a tree and trying to pretend that this Christmas is like any other.
Ask you mum if she is up to contacting the solicitor and acountant or if she wants you to do so. Perhaps your husband will help with this if your mum can't do it herself,
You mum needs to find out what she wants done with the business if it too has been left to her. It doesn't sound to me as if she has ever been part of running it, or as if you and your sister have. So, a priority is to find out what you as a family are going to do about the business. You have three, perhaps four options:
Take it over as a family (not advisable as you and your sister are not on good terms with each other)
Sell it (I don't know if this is possible but the accountant and perhaps the solicitor can advise)
Put in a manager to run it.
Let your sister do what she wants with it
I honestly don't think that right now you would feel less lost without your father or miss him less, if he had been concious before he died, or had had a conventional funeral.
Such a sudden death is very hard to cope with emotionally, so it makes sense to off-load as many of the practical things on the solicitor and accountant as possible.
I hope you soon start feeling just a little better able to cope with things, but don't push yourself too hard.
Have any of you got all electric cars? Pros and cons please.
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