The tech billionaire's eldest daughter, Jennifer Gates, who he shares with ex-wife Melinda French Gates, announced her pregnancy on Thanksgiving.
Jennifer included emojis of a green heart and baby bottle in her Nov.
The pregnancy news comes more than a year after Jennifer and Nayel, 31, tied the knot in a romantic ceremony in New York's Westchester County.
In addition to Jennifer, Bill and Melinda are also parents to son Rory, 23, and daughter Phoebe, 20.
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