I have thankfully never had to do this since moving into home childcare venue

When I worked in a centre parents always KNEW termination was coming if it got to that point - so it was never a 'surprise' and the details could be kept clear and factual in their letter just for our records. Termination in centre care was either due to their child was a danger to the program and we had already had several meetings prior to try to resolve that, given a deadline to meet 'goals' and if they were not than it was a 'as per our behaviour management contract dated (insert date that contract was made) in regards to little X's goals for improvement needing to be seen by today's date we will no longer be able to provide services effective (insert date) and your security deposit has been applied to your account to cover this notice period.

If we were not giving any NOTICE aka the kids behaviour was THAT BAD we would just refund the deposit and end the termination letter with 'care is terminated effective immediately and your security deposit is enclosed in lieu of the two week notice period.'

Now if it was with regards to PAYMENT they would definitely know it was coming cause who doesn't know their account is in arrears? In which case it would be along the lines of 'Please not that effective today we will no longer be providing childcare services. As per our contract you have not kept up with your financial obligations for care and your account is currently in arrears of X amount. Please note that if your account is not paid in full by X date that we will have no choice but to send your account to collections and if that does not resolve the issue to sue for amount owning in Small Claims court."

Is your client AWARE that you are feeling frustrated enough for termination? Is it a payment issue. a behaviour issue or what is motivating the desire to terminate?