Who was the only "big four" character on "The Big Bang Theory" to become a father during the show's run?

Howard Wolowitz, portrayed by actor Simon Hellberg, is the only one of the four main mail characters of the phenomenally popular TV show "The Big Bang Theory" to become a father during the run of the main show. He and his wife, the diminutive and feisty Bernadette, have two children, a daughter named Halley, and a son named Michael.

Howard also has the distinction of being the only character to appear in every episode of the show, and is based on a real person (also called Howard). He certainly has the most adventurous life of the four, including a trip to the International Space Station as an astronaut.

Although he is sometimes looked down on the others (especially Sheldon!) for not having a PhD, he is brilliantly clever in his own way, and also a multi-linguist - including Elvish!

We learn through his voiceover in the prequel "Young Sheldon" that Sheldon and his wife Amy have a son called Leonard, and discover in the final episode of the show that Leonard and his wife Penny are expecting. Whether Rajesh will ever enjoy either married life or fatherhood remains an open question!