/in/isSibling.c:1:1: error: unknown type name 'Bool'; did you mean '_Bool'?
 Bool isSibling(const char * phrase1, const char * phrase2)
 ^~~~
 _Bool
/in/isSibling.c: In function 'isSibling':
/in/isSibling.c:12:32: error: assignment of read-only location '*(phrase2 + (sizetype)i)'
                 *(phrase2 + i) = *(phrase2 + j);
                                ^
/in/isSibling.c:13:32: error: assignment of read-only location '*(phrase2 + (sizetype)j)'
                 *(phrase2 + j) = temp;
                                ^
/in/isSibling.c:22:16: error: 'FALSE' undeclared (first use in this function)
         return FALSE;
                ^~~~~
/in/isSibling.c:22:16: note: each undeclared identifier is reported only once for each function it appears in
/in/isSibling.c:25:13: warning: implicit declaration of function 'strcmp' [-Wimplicit-function-declaration]
         if(!strcmp(phrase1, phrase2))
             ^~~~~~
/in/isSibling.c:26:20: error: 'TRUE' undeclared (first use in this function)
             return TRUE;
                    ^~~~
/in/isSibling.c:30:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^