At what age did your maids stop bathing your kids? Boys especially. Is there a 'healthy' age to put a stop to it?

I think it very much depends on when your child is ready to shower by themselves. Usually by around 5 or 6 (though different children will be different) they should be independent enough and would request to shower by themselves. My niece asked when she was six and my cousin slowly taught her how to clean herself properly. Safety is the key concern so she made sure to explain to her daughter not to play in the bathroom and bought new non-slipped mats. If for any reason you are worried but feel that your child is not old enough to shower himself yet, you can probably take over the task from your maid instead till he is ready to shower by himself.