Are they Jewish? I can see Dan reaching out after their father passed to say that if he ever needed any advice about running the business or whatever, he could always come talk to him.
As for the sister, she'll likely be 27, and while she loves Sammy, she thinks he's a real pain in the ass. She would have happily threatened to kick his ex-girlfriend's ass. I'm not sure about her career-wise, but she's not the sweet little blonde everyone assumes she is. She's pretty sassy and doesn't take shit from anyone. Definitely would not have wanted anything to do with running a deli.