Solved mystery indoor plant

Hello, my mom's been bought this today by my sister.

Can anyone help identify please. I've looked at hundreds of Orchids and can't find owt like it. The flowers ( about an inch and a half across but no " pouch " ) are all on top of an 18" stem which is very thin at the bottom and thick at the top and so isn't very stable. It's growing in a normal walled plant pot in compost.

 

Hi KFF, it's a Dendrobium (here in white)

It's a great plant, always looking lush and exotic and flowers easily and for long periods of time. The stems are top heavy so the plant can topple over unless it's in a heavy pot.

It doesn't have those fat aerial roots which need light, but more "normal" fibrous roots so might do perfectly well in an ordinary pot. Mine is in transparent pot in orchid mix though. Next time I repot it I'll add pebbles in the mix to weigh it down a bit. The stems snap when the plant falls

 

Thanks @Selleri , some great information there. It should be alright in her bathroom window then.