Was the child who played Little Ricky on “I Love Lucy” the son of Lucille Ball and Desi Arnaz?

No. Originally, Little Ricky was played by a doll wrapped in a blanket.

Later, two six-month-old twins, Richard and Ronald Simmons, took the part, followed by three-year-old twins Michael and Joseph Mayer.

The last child to play Little Ricky was Richard Keith, whose real name was Keith Thibodeaux.