Lighthouse

Flesh Golem Cave
In addition to being a roadblock on the critical path to keeping Safana in the party, Sil and the other Sirines at the entrance of the Flesh Golem cave are part of a quest, which can be received after they are killed, but only if the party's reputation is below 14. Once the reputation requirement has been met and the quest received, the reward can be received at any reputation level. The quest giver is Cordyr in Baldur's Gate Docks, and the rewards are, 1000 XP, Reputation +1, and a Flame Arrow scroll if Reputation is 1-7, and Haste scroll for reputation 8-20.

Helm of Charm Protection should be available at High Hedge from Thalantyr; it is in the item listings in the game, but is not implemented. This simple solution being unavailable, the remaining strategies rely on two other factors: Fighters with high HP, and Pets, ie, creatures controlled and/or summoned by the player, especially the Animate Dead skeletons that are immune to Charm. In these scenarios, the Fighter or pet is sent in on their own, and must survive the Sirine's other spells; the distance from the party ensures that the Fighter does not attack any party members. Whether using pet or tank, the strategy behind these tactics is to run the Sirines out of Charm spells. But there is a third option, which is Minsc's Berserk ability. His mind clouded with a killing fury, he is immune to charm effects and will kill the Sirines although control of him is lost.

Links
http://www.forgottenwars.com/bg1/ar3600.htm