From the research I did it seems Force ghosts can appear to whoever they want to

Title: Beginning
author: Cindy Ryan
notes and summary: See part one

The night ticked by with agonizing slowness for Poe. The hospital staff with permission from General Organa had let Poe stay past visiting hours. Not that he was going without a fight. Espeically since her fever had increased slightly a couple hours after dinner. Finn had stopped by then and stayed until visiting hours were done. Poe had told him his theory or the partial theory he'd worked out.

"As crazy as that sounds I don't think it's crazy."

Finn's earlier words echoed through Poe's current thoughts. The fact that his friend didn't shut him down completely said something.

"We all heard the legands growing up, Poe."Finn had stated quietly."Then Han Solo confirmed to Rey and I that all that was true."

Poe knew he was running out of time. He had to find a way to talk to Leia about her son. It would most likely be one of the most difficult conversations of his life, but for Rey, he had to try.

Poe must've dozed off because next thing he knew a medical droid was poking his left arm trying to wake him.

"Sir!"The metallic voice called again.

Disoriented and alarmed Poe sat bolt upright his gaze going to Rey. From what he could tell the monitors looked the same. Poe glanced at the droid.

"What?"Poe asked.

"It's 0600, sir we need to run some tests and do another try with the bacta tank."the droid explained.

"Okay."Poe said as he stood moving to the nearest wall to stand.

0600?Poe thought with surprise He must've been more tired than he thought.

"Sir you need to go and eat something."The droid urged.

Poe shook his head watching as more droids moved Rey to a gurney that hovered near the bed. She looks so small and fraile.

"It will do both of you good."the droid insisted tugging at Poe's left arm."this will take some time we'll call you if there's any change."

Poe's weary brain realized this wi be as good a time as any to talk to Leia.

"Alright."Poe said reluctantly and with a last glance at Rey he left.

General Leia Organa glanced up as the door to her office chimed. She didn't sleep much these days even though her doctor kept encouraging her to do so. Especially with her recent injuries he insisted it was the best thing for her. Leia knew he was probably right but when she closed her eyes the memories assaulted her. Good ones and bad.

"Come."Leia ordered as she continued to work on a data padd.

"General."Poe Dameron greeted as he stepped in and the door slid shut behind him.

"Commander, how is Rey this morning?"Leia asked.

"Not much change from last night. Droids are givng her another bacta tank treatment now."Poe replied quietly.

Leia nodded as she studied the young pilot. He'd showered and changed clothes since she'd seen him yesterday. Though from the worry lines and dark circles under his eyes she doubted he got much sleep.

"You didn't just stop by this early to give me an update."Leia stated motioning for Poe to sit in the guest chair.

Poe did sit down and then almost as quickly jumped back to his feet. Leia didn't need the Force to tell her he was nervous and anxious.

"General."Poe began turning to face Leia as he stood by the right side of the chair. "What I'm about to say may get me in a world of trouble but I need you to hear me out. If I'm right the droids aren't going to be able to help Rey."

"You don't think it's a physical ailment."Leia surmised.

"I think it's physical manifiestation created by the Force bond."Poe replied grimly.

"Created by my son you mean."Leia clarified as she leaned forward.

"Yes."Poe said as he gripped the chair back with one hand. "I don't know how he's doing it but..."

"He's right, Leia."A male voice said from seemingly nowhere.

"What?"Poe asked confused.

Then Luke Skywalker's form materialized in a blue shimmering image in the space between Poe and Leia's desk and Poe jumped a mile backing away.

"Whoa!"Poe exclaimed dark eyes wide.

"He's using their connection to strengthen his power with the dark side and inflict pain on Rey at the same time."Luke continued ignoring Poe's reaction.

Leia rose to her feet walked past her brother's ghost and looked at a picture on the wall near the door. The image was of Han Solo in his younger days.

"How do we stop it?"Leia asked a few minutes later turning away from the picture.

"I have a few ideas."Luke replied.

"Will it hurt her?"Poe asked finding his voice.

"Perhaps, the bond between them is one of the strongest in the Force I've ever seen."Luke stated quietly. "Though I do believe Rey is strong enough to endure whatever happens."

"Let's proceed with your plan."Leia ordered.

Together the three began to make preperations.