• Anderson Cooper said he was furious after missing his son Wyatt's first steps
  • He added that he wished ex Benjamin Maisani would have just lied instead of telling him about Wyatt's milestone 
  • Cooper was on an overseas trip for "60 Minutes" when Wyatt walked for the first time

Anderson Cooper was not happy with his ex Benjamin Maisani, after their 13-month-old son, Wyatt, walked for the first time.

On Wednesday, Cooper, 54, appeared on "The Late Show With Stephen Colbert" where he talked about his son achieving a new milestone while he was on an overseas trip.

"So, just for the first time, I was away in Israel last week," he was quoted by People as saying. "It was my first work trip for 60 Minutes and I was doing an interview and I get this text from Wyatt's other dad, Benjamin, and he said, 'He just walked!!'"

While most parents would have been thrilled, Cooper joked that "My reaction was fury." Instead of informing him of their son's milestone, he wished that Maisani had just lied instead.

"I got really pissed at Benjamin," the CNN anchor continued. "In my household when I grew up, you would lie about everything, so he should have just lied. He should have lied and said, 'Oh no, he's not walking at all,' so when I got home and he walked, we'd be like, 'Oh my god! It's the first walk.'"

Cooper joked that his son walks "like a drunken sailor," adding that while he's talking, it's not exactly in English.

"He talks in a dialect of Hindu or Urdu, I'm not sure," he told the host. "It's incredible. It's a really interesting dialect. He doesn't make any sense at this point, but he's really committed to it."

Cooper welcomed Wyatt, whom he named after his later father, last year. They celebrated his birthday in April, with the journalist sharing adorable pictures of his baby on Instagram.

"Today is Wyatt’s first birthday," Cooper wrote. "I can’t believe it has already been a year. He is sweet and funny, happy and kind, and I love him more than I ever thought possible."

Cooper and Maisani are no longer together, but they co-parent Wyatt and live in the same home. The journalist admitted during a previous appearance on "The Ellen DeGeneres Show" that their unconventional parenting situation is strange but said it "works" for them.

"We actually still live in the same house because we get along really well," he told host Ellen DeGeneres. "It's weird, but it works out."

Cooper also praised Maisani as a dad to Wyatt. He shared that Maisani initially wasn't as sure as him about becoming a dad, but when Wyatt arrived, his ex-boyfriend turned into a "big softy."

"It was interesting, because he wasn't sure he wanted to have a kid, which is one of the reasons we probably broke up. He came around on the idea, and now, he's just such a great parent," the "Anderson Cooper 360" anchor added.

Anderson Cooper
Anderson Cooper is pictured attending the Turner Upfront 2017 at The Theater at Madison Square Garden in New York City on May 17, 2017. Getty Images/Angela Weiss