Joshua Jackson Allegedly Had Concerns About Kid Being Around Jodie Turner-Smith's Bro

Joshua Jackson raised concerns about his daughter being around Jodie Turner-Smith's brother long before three women sued the actress and her bro over his alleged drug-fueled sex parties ... according to the attorney representing the women suing the siblings.

Here's the deal ... Jodie and her brother, Richard Mark Anthony Smith, were sued by three Jane Does who claim Richard pressured them into drug use and nonconsensual sexual activity.

The lawsuit also alleges Jodie knowingly provided her brother with housing, money, and other support despite his alleged behavior. Through her reps, Jodie has denied the allegations, calling them false, and claimed the lawsuit was actually filed by a man who was harassing the actress.

Now, plaintiffs' attorney Nissan Thomas is firing back in a statement to TMZ ... he claims sources close to the family told his office Joshua had concerns about Richard being around his daughter, Juno, who he shares with Jodie.

According to Thomas, those sources allege Joshua's attorneys raised similar issues during the former couple's divorce and custody proceedings. Thomas also claims he was told some of the concerns included Jodie allegedly allowing Richard to pick Juno up from school despite Richard allegedly not having a driver's license.

Thomas says his clients "look forward to their day in court" and intend to present evidence supporting the allegations in their complaint.

We reached out to Jodie ... but she had no comment.