I haven't used this company yet but they are all Phils so I expect they will do a good job. I have a "maid" at the moment who is not working out so keen to try this company after EID.
http://qatarmaids.com/
They provide full-time or part-time and will not only take care of your children, but clean, cook and shop etc! Very professional company. A friend has used them and very happy!
Good luck!