HI-5 have lost their third member in a month, leaving producers scrambling to assemble a fresh line-up for the new year.

Sun Park's departure follows the resignation of the final two remaining original members - Nathan Foley and Kellie Crawford - from the children's group.

The trio will perform with the group for the last time at Channel Nine's Christmas carols in Melbourne on Wednesday night.

"I didn't really see myself doing Hi-5 into my 30s,'' Park, 27, told The Sunday Telegraph.

"I'm getting married next year and some time in the future I'd like to have kids and settle down.''

After forming 10 years ago with the original line-up of Kathleen de Leon, Charli Delaney, Tim Harding, Foley and Crawford (then Kellie Hoggart), Hi-5 has released numerous albums and DVDs.

Their television show is broadcast around the world with spin-offs in the US and UK. The next generation of kids will grow up with the same brand name, but five different faces.

"I never really considered Hi-5 to be a long-term thing,'' Park said.

"I came in thinking I was going to be a temporary placement.''

Unlike the members of rival kids' group The Wiggles, who own their franchise and merchandising rights, Hi-5 members are on salaries paid by production company Southern Star.

Hi-5 ranked fifth on business magazine BRW's annual list of top-earning entertainers this year, raking in $18 million.

The Wiggles, with three of their four original 1991 members remaining, topped the list with $45 million.

Industry rumours suggest Southern Star dropped Foley and Crawford because it wants to recruit younger and cheaper replacements.

Park denied there had been any pressure for any of the members to leave and that it was entirely her decision, adding that "Kelly and Nathan resigned''.

Park has been a member of the kids' group for three years, replacing Kathleen de Leon Jones.

She hopes to pursue more acting roles and has set up the business Empire Music Tuition with fiance Nathan Pezzimenti.

De Leon Jones, Harding and Delaney left over the past two years - de Leon Jones after she had a baby, Harding after a motorbike accident and Delaney to pursue a different career path.

"I kind of just want to be around for my marriage really, and I know it was a problem for Kathleen and Charli as well when they were married,'' she said. "I want to start my marriage being at home and not constantly on tour.''