Ask Gary.

"Hey now, sis, get over here and let me cheer you up," Gary said behind his bedroom door.

Hank and Bernie looked at each other as bed springs shifted inside Gary's room. He gave her a gentle squeeze round the shoulder to reassure her. Their eyes met and each wondered what the other was thinking.

Bernie felt unsettled. Her boyfriend was probably about to have sex with his sister Lil again. She felt...jealous? neglected? But then Bernie had just had another threesome downstairs with Gary's parents and felt a little guilty about that. It was so good to hear Gary say he loved her, but annoyed that Gary admitted that he didn't tell Bernie enough.

Gary's dad Hank felt proud that Lil could confide in Gary about her love life, and that Gary could give her sincere good advice that showed he was thinking about her. Hank never figured his kids would be so close sexually, but it was good they were close and caring.

Lil's sniffles gradually stopped, replaced by coos of pleasure.

"D-do you think we should go in?" Bernie asked Hank, a crease in her brow.

Hank breathed quickly and deeply. His penis throbbed erect as he heard the sounds of sex beginning behind his son's bedroom door.

"We'd better ask now, or it'd be rude to interrupt," Hank said.

"Oh," Bernie said.

Hank cleared his throat. "Gary, Lil?" he called through the door.

"Ooh!" Lillian squeaked in startlement.

"Can Bernie and I come in?" Hank finished. "We don't mean to interrupt. If it's all right, we'd like to join you. And I owe you an apology on behalf of myself and your mom."