Robert Downey Jr. appeared on The Late Show With David Letterman on Thursday night (April 23). In an interview that went smoother than the one he gave the day before, the actor discussed turning 50, how he celebrated the milestone birthday and his youngest child, Avri.

The actor told Letterman and the audience he wanted to show off Avri's "first picture on planet Earth." An image of the gorgeous little girl flashed across the screen at that point. The five-month-old wears a bright yellow bonnet in the photo — and while it's too early to determine whether she takes after her famous dad, we can already see that she has enormous, beautiful eyes and the sweetest little expression.

"We have a daughter named Avri," the actor said. "I have three [kids.] I have a 21 year old, Indio, I have a three year old, Exton, and now I have Avri, who is a little over five months."

"What's the dynamic with this one and the older one?" Letterman asked.

"Well, she's female," Downey said. "Um... and..."

Letterman asked if there's any sort of rivalry brewing between the two younger children.

"Not yet," Downey answered. "It's natural for Exton to want to bite her once in a while and it can start off as a little pet and it can turn into a little nibble... I think it's establishing dominance but then, you know, she'll be running stuff at some point."

Letterman shared his take on parenting multiple children as well. "The first one has everything coming, not a problem and then suddenly there's a little competition. You just have to watch it sort itself out," he said.

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