Poor little thing!

Of course there is the tried and true Calamine Lotion - you should be able to get this at any chemist or supermarket.

Or, if you dont want to leave the house...

Toothpaste. Good old fashioned toothpaste. Takes out the sting and helps reduce the swelling and redness.
Just rub a little paste on and around the bite til its almost rubbed in and leave it!

And a good preventative - instead of Rid! - we use 1 part dettol to 1 part oil, mix really well in a spray bottle and spray it on her skin - mozzies HATE it!
Good luck!