Hard to say, as kids did not use to feature on the Archers except off stage. Only when they reached adolescence did we start to hear their voices. (And Judy Bennett (Shula) was one of several actresses who used to portray kids of both sexes in radio drama)
I do, however, have a v clear memory of Lillian at ~14 wanting a pony so so much (rather like Tony and the car) - we were all led to believe she wouldn't get one, and so was she - and then on ?Christmas morning she was led outside and there was A Pony! (can't remember his name). As Lillian is a couple of years older than me and her name rhymes with mine I kind of identified with her.
Hmm - how old would Tony have been then?