Raising my Rates

I've realized that I am woefully undercharging after speaking with some other nannies. I need to raise my rates and will need to notify several families. Typically it's difficult to have important conversations with children present, so I plan on emailing them. I was charging $30 for 2 kids but I plan to start charging $38. I think this will not be an issue for Parents, I just need help with wording the email.

"Hello Parents,

This email is to notify you that I need to change my rates starting this Monday. I realized that I have been undercharging. The new rate for 2 children will be $19/hr per family. This rate reflects my experience and quality of care the children receive, as well as the effort that goes into caring for 2 kids. I really appreciate working with all of you and love caring for your children.

Sincerely..."