It probably has already been talked about, but. The lost boys are special, they are set apart from other typical horror movie antagonists because they care about each other. They love each other.
This is proven by three moments;
The Frog brothers are a target for Paul. Reasons could have been; they were a danger to Paul, or they had simply gotten Paul's attention by getting close to him. This line proves otherwise. Paul does not want to kill the Frog brothers for himself, but as an act of vengeance for Marko. One of the other boys death affected him enough to push him to do something about it.
Let's go through the scene;
The other three boys are woken up, David screams "You're dead meat!"
He chases the Frog brothers and Sam up to where the sun shines. David gets burnt and has to let them go. He screams and lets go.
One tear falls from his eye. He laughs, "Tomorrow."
The first thing to note is how David doesn't laugh right away. It doesn't match his behavior in his previous hunting scene, where he laughed before going to kill. Instead, he screams. The laugh he gives in the end is also far from what it usually is. It's not loud or joyous.
Like with the previous point, it could be taken as David defending himself, and the tear could be thought to be of pain. But, narratively, the tear isn't necessary to tell he suffered from the burn, he already reacted. A new information it could give would be sadness, or shock, which would be towards the death of Marko.
3. The boys looking for eachother
This is the first scene of the movie, which is used to set the tone and the plot of the movie. It is also the boys' introduction, in which relationships and personalities are explained to the viewer in the most efficient way possible.
David comes first, as the leader. He looks around and sets the path for the other three. Dwayne and Paul follow, and they both turn towards the lasts, with a smile. This explains that the Boys don't just hang out because it's convenient or because they have too, they actively want to stay together. Dwayne and Paul make sure everybody is following and sticking close.
This genuine care the boys have for eachother is the most important reason for why people like them so much as characters. It gives the boys a deeper dynamic, a feeling of group instead of staying individuals.
It also gives dimension to the characters. They cannot be simple animalistic killers with the only desire to stay alive, since they love. This opens a gate. What else do they feel? How 'human' are they? Since so little is seen of the boys, it's free to be intrepreted and imagined as anyone wants.
In short, the boys are brothers <33333 and that's why everyone loves them.
