The Hopoates are poised to become the first family to have five siblings play NRL and NRLW this century, with teenager Lehi to debut for Manly against Melbourne.
Sea Eagles coach Anthony Seibold confirmed on Thursday fullback Tolu Koula will miss the match with a shoulder injury, opening the door for Lehi Hopoate.
Hopoate could debut at fullback where he has played most recently in NSW Cup, while another option is for him to play centre if Reuben Garrick moves to the back.
The news came as Seibold also admitted he is weighing up playing Tom Trbojevic at centre when he returns from injury in July, as Manly try to look after his body.
But Seibold's more immediate focus is Melbourne, when Hopoate - the youngest of eight children of ex-Manly winger John Hopoate - will play his first NRL match.
The 19-year-old will follow brothers Will, Albert and Jamil in having played in the NRL, while his sister Kalosipani has played 13 NRLW games for the Sydney Roosters.
The list takes them beyond the four Sims that have played NRL and NRLW this year, and beyond the quartets from the Burgess, Mata'utia and MacDougall families.
Historically, the Quinlivan brothers of the 1930s and 1940s, as well as the Cooper brothers of the 1940s and 1950s, also had five siblings play at the top level.
"It's really special. He's a terrific young kid," Seibold said of Lehi.
"He did the pre-season with us and he did such a good job we took him out to Vegas just for the experience.
"You see a lot of young outside backs coming into the game at the moment, full of speed and energy and that high-tempo type play."
Lehi's debut comes as Manly prepare to face a Storm side missing Ryan Papenhuyzen and Cameron Munster, while halfback Jahrome Hughes is expected to play.
Manly are also without Matt Lodge (biceps) and Lachlan Croker, who is out indefinitely with an inner-ear issue after suffering a concussion three weeks ago.
"The good thing is it's got nothing to do with the brain," Seibold said.
"But it could be days or it could be weeks to try and clean that up. He's been a little bit up and down with regards to how he's been feeling."
Seibold also confirmed the biggest change at Manly in eight years looms, as he weighs up how to play Trbojevic when he returns from his latest hamstring issue.
At his best Trbojevic remains one of the top fullbacks in the NRL, but Seibold is mindful of the toll it is putting on the superstar's body.
"Turbo and myself have had conversations around what we can do to help him," Seibold said.
"We'll see how Tolu goes at fullback over coming weeks and see how Turbo's feeling about his body.
"His best position has always been fullback.
"But he's done a really good job at Origin level as a centre and I think he could play as a No.6 at some stage in his career as well."
