You can add conditions to your relationships

 1class User
 2{
 3    public function posts()
 4    {
 5        return $this->hasMany(Post::class);
 6    }
 7 
 8    // with a getter
 9    public function getPublishedPostsAttribute()
10    {
11        return $this->posts->filter(fn ($post) => $post->published);
12    }
13 
14    // with a relationship
15    public function publishedPosts()
16    {
17        return $this->hasMany(Post::class)->where('published', true);
18    }
19}

Tip given by @anwar_nairi