JR Ewing (Larry Hagman), Bobby Ewing (Patrick Duffy) and Sue Ellen Ewing (Linda Gray) have all reprised their roles in TNT's revamp of the '80s soap.
"We're just breaking stories [for season two] now so I don't really know [who we might bring back] yet," Cidre explained to TV Guide.
The showrunner named Gary Ewing (Ted Shackelford) and Valene Ewing (Joan Van Ark) as two characters she is interested in bringing back.
"I just met Joan Van Ark the other day and she was lovely," Cidre admitted. "We tried for a cameo with her and Ted Shackelford this past season, but it didn't work out.
"I also met Donna Mills [from Dallas spinoff Knots Landing] and she looks awesome, but I don't know that we can use Knots Landing characters."
The first season of the new Dallas concluded in the US on Wednesday night (August 8), with the finale episode attracting 4.29m viewers.
The series will launch on Channel 5 in the UK next month.
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Watch a trailer for the new Dallas below: