Kids boat?

I'd have said a Splash would be much too much for a 36kg, 5ft sailor. It didn't seem inappropriate for me when I sailed it and I'm 65kg and 5' 9" and I'd agree with Nick A that it's more a Radial alternative (albeit shorter, slower and more rolly than the Radial which I preferred).

Personally I think the Topper is a cracking little boat - great fun yet pretty vice-free, and even quite small kids seem to be able to right it when capsized - surely a very important confidence point. I'm sure that at 85kg you're better off with a Pico, Nick, but for someone less than half your weight...

I thought the Tera was more of a pointy-bow alternative to the Optimist rather than the Topper, and at 36kg maybe that's the territory your sister is in, but if she can handle a Topper (maybe with the small sail or reefed at first) then that's the one I'd go for.

The splash is a great boat - but more a laser radial alternative than a topper / pico alternative surely.

I'd go for a pico over a topper 'cause it can take two, has a bit of a jib, has a racy sail option and is suitable for adults in huge winds (and it'll certainly plane in a force 7 even with 12 stone in it!).

The terra looks really good though - and exceptional value too.  Are they making them abroad using slave labour perchance?

The Mirror would make an excellent double handed option,  particularly if your sister likes to sail in company,  certainly a bit more sociable and many kids enjoy the confidence of having someone else in the boat.

For your budget you will get a well sorted Mirror,  epoxy coated so minimal maintenance.  A bit more money will get a modern GRP Mirror.

See 

www.ukmirrorsailing.com