The Miracle video is such a cool idea. The video shows children maybe 11 years old miming to the song The Miracle and the child who portrays Freddie, his costume is constantly changing between four outfits that Freddie famously wore.
You see a long haired "Freddie" sitting at the piano and singing in his black and white diamond leotard from 1977, also you'll see a (mistakenly) mustached "Freddie" dressed in the gay biker outfit from 1978. Another "Freddie" can also be seen in his Live Aid getup from 1985. At last we can also see "Freddie" dressed in his Live At Wembley yellow jacket outfit. The rest of Queen dressed the same throughout the video.
The video was released in 1989, you are correct Ross McCall starred as "little Freddie Mercury:. McCall was born in 1976 so he was roughly 12-13 at the time.
Beyond this, not much else seem to be known about the other young actors. The kids in the 'Miracle' video were chosen after an audition (needless to say that many, many kids showed up). Unfortunately, nothing is known about them, except for the fact that they were professional actors, and still are.
https://en.wikipedia.org/wiki/The_Miracle_(album)
http://www.imdb.com/name/nm0564680/
