Jack and Indie Bostock could share NRL and NRLW grand final day in Sydney if both win their preliminary finals this weekend.
Jack faces the Sydney Roosters at Suncorp Stadium on Friday night, while Indie's Gold Coast team hosts Brisbane two days later.
The Dolphins centre has won all 15 matches since returning from an ACL injury, while Indie has remained unbeaten for 10 games after missing Gold Coast's opening-round defeat by the Roosters.
"I'm glad he is playing first so if he breaks (the winning sequence) then there is no pressure on me at all," Indie grinned.
"I like that we are winners in the family but I am trying not to think too much about it because it is going to start getting competitive."
A successful weekend would give the siblings a combined 29-match unbeaten run and place them together on grand final day.
"That would be pretty special for the family," Jack said.
"We are both very supportive of each other and both want to see each other there on grand final day."
Their father, Josh Bostock, played wing for Balmain and watched Jack's first finals victory, a 26-16 win over the Warriors in Auckland.
"My dad takes most of the credit for it," Indie said.
"My mum grew up a netballer so she can't really say much. Dad likes to say he has some super gene."
Indie's partner, Dolphins winger Tevita Naufahu, could add another family celebration by helping Redcliffe beat Sunshine Coast in Saturday's Queensland Cup grand final.
That result would send Naufahu into the NRL State Challenge final in Sydney.
"That would be really sick if that did happen. Hopefully it does," Indie said.
Indie, 19, has scored eight tries in 10 matches since joining the Titans after leaving St George Illawarra without a contract.
Jack, 23, made his NSW debut in the winning State of Origin decider and was selected in Australia's 40-man preliminary World Cup squad.
He is off contract after next season but has indicated he wants to remain with the Dolphins.
"I want to stay," he said.