Grace's niece Fiona is portrayed by Billie Lourd. Lourd is the real-life granddaughter of Debbie Reynolds, who played Grace's mother (Fiona's grandmother), Bobbi Adler.
Jack is wearing glasses on the plane but had laser eye surgery two episodes ago (E7 - What a Dump)
Billie Lourd plays Grace's niece. Billie Lourd's parents are Carrie Fisher and Bryan Lourd. Bryan left Carrie to be with a man.