Robert Irwinsays pregnant sisterBindi Irwinwas pretty forgiving over himaffectionately calling her “massive"on live television.

Earlier this month, during an appearance on Australian morning showSunrise, 17-year-old Robert and his momTerri Irwintalked about their seriesCrikey! It’s the Irwins, as well as Bindi’s first pregnancy. Terri, 56, said Bindi, 22, is in that “sweet spot where you really miss being able to see your shoes.”

Laughing and blushing, Robert joked, “She’s not here now.” Later in the interview, he admitted, “I’m in so much trouble. I’m in so much trouble — don’t tell her about this, please!”

Speaking withAccess Hollywoodon Thursday, Robert admits he has a “knack for just absolutely putting my foot in it on live television — let’s hopefully not do that today!”

“I called Bindi massive because I think it’s a point of pride,” Robert explains. “Sheis, like, pretty big, so I thought it was pretty cool! She took it pretty well, but I’m really measuring my words now.”

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RELATED GALLERY:Sweetest Photos from Bindi Irwin’s Pregnancy

Sharing themoment on Twitterearlier this month, Robert wrote alongside the video, “Haha… woops,” and Bindi then responded,replyingto her little brother: “‘Don’t tell her about this’ …. 😂 Thanks Robert! Love ya!”

Bindi firstannounced her pregnancy newson Instagram back in August and kept fans up to date on her experiences on the road to becoming a parent.

RELATED VIDEO: Pregnant Bindi Irwin Says Late Father Steve Would Have Been a ‘Perfect’ Grandpa

As for what Bindi’s child will call Robert? “Robert has decided that ‘uncle’ needed an upgrade and he’s now calling himself the ‘funcle’ which means ‘fun uncle.’ I love it!” Bindi recently toldThe Bump.

Bindi also opened up to The Bump about her plans for motherhood and how she wants to parent her first child.

“I want to give our daughter the opportunity to experience as much as possible in the world to set her up for life,” she said. “The greatest gift my parents ever gave me was their unconditional love and support. They encouraged me to travel my own path while always being there to lend support if I needed it.”

source: people.com