That was Poltergeist and she didn’t end up flushing the bird but burying it in their back yard.
Yes-as I said, she was preparing to flush the unfortunate bird when her daughter caught her in the act, and after seeing the girl’s horrified face, Spielberg did a straight cut to the burial scene!
That was what made it so funny to me...:)
(That, and the Golden Retriever immediately trying to dig the dead bird up to either roll on it or eat it!)