There is something odd about all this OP.
When you purchase a house, you do not sign the Deeds. You sign a Contract and TR1 form. These are signed in the presence of witnesses who also sign.
Once the contracts exchange then complete, monies are transferred and then the solicitor arranges the registration at the Land Registry of the Title Deed of the property, which nowadays is registered electronically.
So you need to be sure:
(1) did you sign as a purchaser or a witness when the property was purchased
(2) in what names was the property then registered at the Land Registry
Do you have a copy of what you signed? As a purchaser you should do, as a witness, you won't.
It doesn't sound like you have properly understood this paperwork process.
Finally, you do not have an automatic right to ownership of the house if you have not made any financial contribution. Nor do you have any automatic right to inherit and neither do your children.
I suggest you see a conveyancing solicitor who can take a look at the history and any paperwork you have and advise you properly of your position.