Brian To / WENN 1 / 6
Brian To / WENN 1 / 6

In case you didn't know, Dax is off the market. Dax Shepard joked about why he decided to get a bell tattoo in honor of his wife Kristen Bell during an appearance on "The Ellen DeGeneres Show" on Thursday, Sept. 18.

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"I don't like wearing jewelry, but I felt obliged to warn all the men that I'm taken," the 39-year-old said. "So, I thought a tattoo would be fitting. And her last name conveniently is an object I could tattoo. And there's little letters in there."

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The "Parenthood" actor gave DeGeneres a closer look at his black ink on his right finger, which also has the letters K, L, and D to represent the couple and their 17-month-old daughter Lincoln. "So Kristen, Lincoln and Dellen DeGeneres," he teased.

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Us confirmed in June that Shepard and the "Veronica Mars" alum, 34, are expecting their second child. "We are building a circus," he told the daytime talk show host. As for whether it's a boy or another girl? "It's going to be a surprise," he quipped, "to America."