Sean Lowe and Catherine Lowe rehomed their family dog after the Bullmastiff sent one of their three children to the emergency room.

The “Bachelor” alum told his Instagram followers Wednesday that the canine, named Gus, bit his son Samuel on the side of the head when the 6-year-old bent down to pet him several weeks ago.

“The result was a trip to the E.R. and a staple in the head,” the former reality star, 39, recalled.

“So as much as I love that dog, I have to protect my kids first,” he continued on his Story, explaining that Gus now lives in a “great home” with his dog trainer.

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Sean, who admittedly “died a little on the inside” giving Gus away, noted that there were “a couple [other] instances of resource guarding in the past.”

After the pooch “snapped at/bit” daughter Mia, 3, Sean and Catherine “did everything in [their] power to keep it from happening again” — but couldn’t ignore their pet’s repeated “lapses in judgment.”

The “Bachelorette” alum assured his followers that Samuel is “doing great” and has “fully healed” from his injury.

“He misses his dog too. And so do his brother and sister,” Sean added, referencing Mia and his 4-year-old son, Isaiah.

As for whether the self-proclaimed “dog lover” and Catherine, 36, are considering adopting another in the future, Sean would feel like he “was cheating on Gus.”

He explained, “We’re going to take a break. … I still believe Bullmastiffs are absolutely amazing.”

Gus was a puppy when the family of five brought him home in April 2022.

“Well, Mia had a nice 2-year run, but that run is now over. Please say hello to my new favorite child, Gus,” Sean joked via Instagram at the time.

As for Catherine, the graphic designer called Gus “another sweet boy to love” in a post of her own.

She and Sean met and fell in love on Season 17 of “The Bachelor” and have been married since January 2014.