The TV series, "Lassie", started in 1954 and ran for four seasons with Tommy Rettig as Jeff Miller and Jan Clayton as his mother. You can search "Tommy Rettig and find some information, but when you click on "Lassie" in his filmography, you are taken to the Jon Provost series that began in 1958. Actually, the way IMDb has it configured is very confusing. The Rettig/Clayton and George Cleveland as Gramps series was better by far. Jon Provost was a bit of a chip, and our family actually stopped watching after a few episodes.