some progress

app/Models/Site.php

@@ -53,4 +53,14 @@ class Site extends Model
     {
         return $this->hasMany(DnsRecord::class);
     }
+
+    public function domains(): HasMany
+    {
+        return $this->hasMany(Domain::class);
+    }
+
+    public function sitemaps(): HasMany
+    {
+        return $this->hasMany(Sitemap::class);
+    }
 }