He also took a moment to thank his girlfriend, Jan Svendsen, for being the "sunshine" of his life.
A stunned Svendsen then made her way up to the stage where Weiss formally asked her to marry him, placing his mother's engagement ring on her finger after she said yes.
Glenn Weiss, victor of the Outstanding Directing for a Variety Special award for 'The Oscars, ' and Jan Svendsen kiss after getting engaged onstage during the 70th Emmy Awards.
'And to my sister and brothers, I didn't swipe it dad knows I have it!' he laughed.
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"Part of my heart is broken; I don't think it will ever be repaired..." "I want to put this ring that my mom wore on your finger in front of all these people and with out parents watching from above". Weiss said to Jan in the audience. "Will you marry me?" She said yes and the two kissed as the audience cheered.
'Thank you to the academy!' a clearly delighted Weiss said as he and his new fiance left the stage to a standing ovation.
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"The Emmy goes to Glenn Weiss for the Best Reality TV moment of 2018 and Best proposal", said another.