I am sorry to hear about this matter. Unfortunately when your mother passed, the estate would likely have passed to your father. Firstly, you will need to see what is contained in the Will, I don't see the grounds. you would have to contest thee Will as you were not reliant on his estate being estranged. With that being said, there is legislation which provides statutory rights for children. Under law in Scotland you and your siblings are legally entitled to a share of one third of any moveable estate (but not heritable estate). The solicitor dealing with the estate should have tried to contact you. I would be happy to look over the Will for you once you have obtained a copy. It should point out who is the executor of the estate.
I shall provide you with a helpful link that will assist you in finding a solicitor/representative near your local area. This will provide you with someone nearby your area who can assist you if required.
I hope this information proved helpful. You will find a local solicitor who deals with these matters on the law society webpage which is as follows;
https://www.lawsoc-ni.org/solicitors (N. Ireland)
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