Simple Main Predicate Example in Prolog

I decided to start playing with Prolog (SWI-Prolog). I wrote a program, and now I'm trying to write a simple main predicate so that I can create a .exe and run the program from the command line. That way, I can find true/false relationships from the command line rather than from the prolog GUI. However, I am having trouble understanding what actually goes in the main predicate. Here is the program so far:

mother(tim, anna).
mother(anna, fanny).
mother(daniel, fanny).
mother(celine, gertrude).
father(tim, bernd).
father(anna, ephraim).
father(daniel, ephraim).
father(celine, daniel).

parent(X,Y) :- mother(X,Y).
parent(X,Y) :- father(X,Y).
ancestor(X, Y) :- parent(X, Y).
ancestor(X, Y) :- parent(X, Z), ancestor(Z, Y).

First Try:
I put all of the relationship definitions in a predicate called family_func() .Then, I tried to call that function from main by typing main . into the command line. I expected to be able to start finding relationships like I did before I created the predicates, but instead, the program started with this error:

  ERROR: c:/.../ancestor.pl:18:0: Syntax error: Operator expected

Here is the code:

family_func():-
    mother(tim, anna).
    ...

    parent(X,Y) :- mother(X,Y).
    ...

main:-
    family_func().

Second Try:
I tried putting all of the definitions in the main predicate. I expected to be able to type main. and then have the program pause and wait for me to start entering clauses (almost like in Java where you run a program and it waits for user input). Instead, when I typed main., it returned false.

Question 1:
I am used to writing code in Java. So, in my mind, The first thing I tried should work. I basically defined local variables in family_func() and then I called smaller "methods" (ie parent(X,Y) :- mother(X,Y). ) that should find the relationships between those variables. When I call main, at the very least, I would have expected the program to wait for me to enter the relationship, return the result, and then close. Why doesn't this work?

Question 2:
How would I actually write a main predicate? Are there any good examples for a program like this? I've tried the example here, but couldn't get it to work.

Thanks for any help.

Edit:
New Attempt - main. returns false, and running parent(tim, anna). right after running main. returns false even though it should be true.

:- dynamic mother/2.
:- dynamic father/2.

family_func:-
    assert(mother(tim, anna)).
    assert(father(tim, bernd)).

parent(X,Y) :- mother(X,Y).
parent(X,Y) :- father(X,Y).
ancestor(X, Y) :- parent(X, Y).
ancestor(X, Y) :- parent(X, Z), ancestor(Z, Y).

main:- 
    family_func.

Edit:
Just in case anyone else needs to know, as @CapelliC states in the comments under the answer, there needs to be a comma between calls. For example:

family_func:-
    assert(mother(tim, anna)),
    assert(mother(anna, fanny)),
    assert(mother(daniel, fanny)),
    assert(mother(celine, gertrude)),
    assert(father(tim, bernd)),
    assert(father(anna, ephraim)),
    assert(father(daniel, ephraim)),
    assert(father(celine, daniel)).

---

我认为应该是（不允许空的参数列表）

:- dynamic mother/2.
... other dynamically defined relations...

family_func:-
    assert(mother(tim, anna)).
    ...

% rules can be dynamic as well, it depends on your application flow...
parent(X,Y) :- mother(X,Y).
    ...

main:-
    family_func.

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