Under the Protection from Harassment Act 1997 is says:
1Prohibition of harassment.
(1)A person must not pursue a course of conduct—
(a)which amounts to harassment of another, and
(b)which he knows or ought to know amounts to harassment of the other.
[F1(1A)A person must not pursue a course of conduct —
(a)which involves harassment of two or more persons, and
(b)which he knows or ought to know involves harassment of those persons, and
(c)by which he intends to persuade any person (whether or not one of those mentioned above)—
(i)not to do something that he is entitled or required to do, or
(ii)to do something that he is not under any obligation to do.]
As such it is an offence.
So report it to the Police. They can issue a harassment warning to father.
If he breaches it then he can be prosecuted in Court.
That should resolve the matter for you.
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