Although George thought Arnie went to get some beer, Arnie actually had sex with Ella, as he considered her younger self to be a "tomato", unknowingly concieving Arnold. When George and Arnie returned to their own time and George decided to leave things exactly as it was. Arnold arrived at the Health Centre with Ella and Stanley, Ella announced that he had come to stay. Janet introduced him to a shocked George, who confronted Arnie. After Arnie confessed, George told Mrs. Raven that Arnie would like to book himself in for a vasectomy, and she'd need a couple of bricks, in the manner of an Ultronian vasectomy when a man has child but not with his wife. (Time and Time Again)
- There is some information missing about Arnold.
- Whether he has superpowers or if his half-Ultronian heritage is known to Ella. As Arnie's powers were removed by the Ultron Council, Arnold too may not have powers, however, powers may be in the Ultronian genome. It is also possible that Arnie's lack of powers means that Ella's pregnancy lasted the proper nine months instead of the Ultron labor of six days. Although, it is possible that Arnold has superpowers and/or only spent six days in the womb, Ella might have covered this up as Stanley's smile to Arnold suggests he thinks he is his real father.
- It is also left unclear whether George repaired the alteration and erased Arnold from history. However, before finding out, George did decide to leave things as it was. Seeing as how Janet said that George never met Arnold shows that his existance did not alter George's history with Janet. However, Arnold doesn't appear in Series 5 and 6 although Ella says he came to stay, although it is possible he could have soon left.