Slap Happy Pappy (1940)

Porky runs a farm; we see him plowing the fields. But it's primarily a poultry farm; as the sign says, "For sale: Miracle eggs if it's a good egg, it's a miracle." A rabbit, doing a Jack Benny impression (Jack Bunny), paints and inspects eggs. He starts to smash and reject a black egg, but it hatches into a black baby bird doing a Rochester impression. We next visit the Eddie Cackler family, (Eddie Cantor) who have been trying without success to have a son; the next five eggs hatch, and they are again all girls. A Bing Crosby lookalike comes by with a stroller full of sons, and Eddie asks for his secret; he demonstrates by crooning to a chick, who lays dozens of eggs with boys names on them. Eddie croons to his wife, but in a higher pitch, then dances out singing the theme song to other caricatures. The egg hatches, but in answer to Eddie's question, is it really a boy? "Mmmm... could be."