Merge two Firestore QueryStream

Question

I'm trying to create an Instagram feed, for this I have two queries, one that fetches all public posts, and the other one brings private posts from users that I follow.

I have trouble merging both my Stream, and still have a Stream<QuerySnapshot<Map<String, dynamic>>> at the end. I tried to use rxDart, but I feel I'm out of options.

  Stream<QuerySnapshot<Map<String, dynamic>>> getUserPostsByUuid(
      {String? userUuid, List<dynamic>? followers}) {

     List<String> acceptedFollowersUuid = [];

      if (followers != null) {
        for (var follower in followers) {
          acceptedFollowersUuid.add(follower['uuid']);
        }
      }

      final _firestoreSubscribe = _firestore
          .collection('posts')
          .where('userId',
              whereIn:
                  acceptedFollowersUuid.isEmpty ? [''] : acceptedFollowersUuid)
          .orderBy('timestamp', descending: true)
          .snapshots();

      final _firestorePublic = _firestore
          .collection('posts')
          .where('isPublic', isEqualTo: true)
          .orderBy('timestamp', descending: true)
          .snapshots();


      // Should return a Stream<QuerySnapshot<Map<String, dynamic>>> with data from both _firestorePublic & _firestoreSubscribe without duplicate.
      return _firestorePublic;

  }