I have several swords. Some are light and nimble, at least for an adult, like my Messers are all around 800g, 90cm-ish in length, with point of balance at around 11-13cm. I think a child should have no problem wielding them if they do it with care. Then there is a 170cm Zweihänder, weighted about 3kg, PoB at 11cm. I have no doubt a child would be able to lift it, but to use it, it would be very hard. If she can use that adult-size-looking-sword in the picture then she definitely earned it. ;)
I have several swords. Some are light and nimble, at least for an adult, like my Messers are all around 800g, 90cm-ish in length, with point of balance at around 11-13cm. I think a child should have no problem wielding them if they do it with care. Then there is a 170cm Zweihänder, weighted about 3kg, PoB at 11cm. I have no doubt a child would be able to lift it, but to use it, it would be very hard. If she can use that adult-size-looking-sword in the picture then she definitely earned it. ;)