Rose Byrne's oldest son went through ''trauma'' after being introduced to his newborn baby brother.
The 39-year-old actress gave birth to her second son Rafa eight months ago, and has admitted that when he was first born, her eldest child Rocco, two, ''didn't quite get'' the concept of having a sibling.
Rose - who has both her children with husband Bobby Cannavale - said: ''There was a bit of an adjustment at first, Rocco didn't quite get having the brother. He would sort of wake up in the morning and go, 'no Rafa, no Rafa'. It's quite a trauma on them the first few months. But it's good, it toughens them up, right?''
The 'Peter Rabbit' actress admits her home is more ''hectic'' now there's a new addition to the family, and says it's Rafa who causes the most fights between the two siblings, as they're always telling the tot to ''take it easy''.
Speaking during an appearance on 'Live! With Kelly and Ryan' on Wednesday (15.08.18), Rose said: ''It's pretty hectic. It's funny, the little guy is a lot more aggressive than the big guy. He just goes in for the tackle and loves to pin him down. [Rocco is very patient], he's kind of like 'Oh get away from me'. And we're like 'Rafa take it easy! Take it easy!'''
Meanwhile, the 'Bridesmaids' star and the 48-year-old actor previously revealed they chose Rafa's unique moniker as homage to Bobby's mother's side of the family, who are of Latin decent.
He said: ''I hadn't given one of my children a Latin name yet, so I wanted to honour my mom's side of the family. And, you know, Rafael Nadal had such a great year and we were constantly keeping up with him and watching all his matches so we were like, 'How about Rafa? That goes well with Rocco.' And that was it.''