Robert Irwin Affectionately Calls Pregnant Sister Bindi 'Massive' on Live TV — and Mom Scolds Him!

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

Bindi Irwin is currently expecting her first child with husband Chandler Powell

Robert Irwin has some explaining to do!

During a live TV appearance on Australian morning show Sunrise on Tuesday, the 17-year-old and his mother Terri Irwin talked about their series Crikey! It's the Irwins, as well as sister Bindi Irwin's first pregnancy. Terri, 56, says Bindi, 22, is due sometime next month, adding that her daughter is in that "sweet spot where you really miss being able to see your shoes."

Robert then says with a laugh, "She's massive now!" prompting his mom to gently scold him by nudging his arm. Trying to remedy the affectionate gaffe, he says, "Like, in a good way! No, like, it's special!"

Laughing and blushing, Robert jokes, "She's not here now." Later in the interview, he admits, "I'm in so much trouble. I'm in so much trouble — don't tell her about this, please!"

Sharing the moment on Twitter, Robert writes alongside the video, "Haha... woops," and Bindi then responds, replying to her little brother: "'Don't tell her about this' .... 😂 Thanks Robert! Love ya!"

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Sunrise Live

Sunrise Live

RELATED GALLERY: Sweetest Photos from Bindi Irwin's Pregnancy

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

Reacting to news of her daughter's pregnancy, Terri shared in August that her late husband would undoubtedly be proud of Bindi becoming a mom. Steve (aka the Crocodile Hunter) was killed during a diving expedition off the coast of Australia in September 2006 at age 44.

bindi Irwin/ instagram

"This is the best day ever! I am over the moon to announce that @BindiIrwin and @chandlerpowell9 are going to have a baby! Words cannot express the love that is filling my heart," she wrote on Twitter at the time. "While I wish that Steve was here to share this beautiful moment, I know that he would be so proud."

In October, Bindi honored her younger brother, writing that he would soon make for an outstanding uncle. "Shoutout to my little brother (who definitely isn't 'little' anymore) for being such an incredible friend," she wrote alongside a snapshot of the siblings hugging. "You're always there for me and I know you will be the best uncle when our baby girl is born. Love you."

Chandler Powell, who married Bindi last year, wrote on Twitter Wednesday, "Not long now until there's 3 of us going on adventures," alongside a photo of the soon-to-be mom and dad.