Blue Ivy Carter is 18 months old now, but the baby joy -- and tears -- haven't stopped for her proud parents Beyonce and Jay-Z. Indeed, in a new, emotional commercial for his album Magna Carta Holy Grail, Jay-Z is seen choking back tears speaking with legendary music producer Rick Rubin about his little girl, whom he and Beyonce, 31, welcomed after a miscarriage. "[She's] something that we both created, you know, we still marvel at her," the rapper, 43, says.

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The toddler, and Jay-Z's intense pressure to be a present and loving father (rejecting the bad example set by his own dad) inspired the song "Jay Z Blue," he continues in the frank chat with his friend.

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"It deals with, you know, my pop left when I was young, so he didn't teach me how to be a man nor how to raise a child or treat a woman," Beyonce's husband of five years confesses tearfully. "So, of course, my karma, the two things I needed I don't have, right?"

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"And I have a daughter," the emotional mogul says. "It's the paranoia of not being a great dad."

Watch the sweet video now.

This article originally appeared on Jay-Z Almost Cries About Blue Ivy: Beyonce and I "Still Marvel at Her"