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They may be getting sworn into the Senate today, but for Kirsten Gillibrand (D-N.Y.), Sen. Chris Murphy (D-Conn.) and Ted Cruz (R-Texas), their kids were the ones who stole the show.

First was Gillibrand's son, held atop his mother's hip as she lightly touched the Bible during a mock swear-in with Vice President Joe Biden.

Midway through the oath, Gillibrand's son reached out his hand and ruffled his mom's hair. With a big smile, Gillibrand proceeded with the oath as she tried to tamp down her hair.

Then came Murphy, who carried his son in one arm as he participated in the mock swear-in. (The real swearing-in occurs on the Senate floor; this particular one is a re-enactment for families, friends and photos.) As Murphy lifted his hand to take the oath, the toddler raised his hand as well, providing a perfect photo op for Murphy and his young son together being sworn in as a senator.

And as Catherine Cruz, the youngest daughter of the new Republican senator from Texas, started to cry, Biden quickly picked her up and joked about himself, "That's a Democrat, I know but that's O.K."

Cruz's wife Heidi quipped back, "She cries loudly for Republicans too."

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