James Middleton Shares That Son Inigo Has Reached a Major Milestone — and That the Family Dogs Had Something to Do with It!

James Middleton is sharing a rare comment about his son Inigo — and revealing one of his new habits in the process.

The younger brother of Kate Middleton , 37, revealed in an appearance on Love Your Weekend that Inigo, 1, has a newfound appreciation for tennis balls.

"He loves tennis balls because there are always some tennis balls around," James said. "He likes to throw the balls for the dogs now, so he sits there and chucks the balls in fits of giggles."

"It's really wonderful, because the dogs have really welcomed him," he continued.

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James, a well-known dog aficionado, also opened up about Inigo's first birthday — and shared that his firstborn, who he shares with wife Alizee, is starting to walk with the help of the canine members of their family.

"He's been on all fours, and now he's walking," James said. "He gets stability by holding on to the back of a dog, and basically they start walking and he doesn't really have a choice, so he starts walking."

In an interview with Hello! , James said he and Alizee — who he has been married to since 2021 — haven't ruled out the possibility of another child. Older sister Kate is mom to three children with husband Prince William , and his other older sister, Pippa Middleton , is also a mom of three with husband James Matthews.

James told the outlet he would love to expand his family "if we're fortunate enough to be able to," he said, saying he was anticipating "the pitter-patter or two or four feet — but who knows which will come first?" alluding that another dog might be in the family's future.

"No matter how much people say to you about how wonderful it [parenthood] is, or how it will change your life, nothing can ever prepare you for that experience of seeing a little baby that's yours arrive," James said. "It unlocks something in your heart that you didn't know was there."