Memorial service Do-It-Yourself
It is common to ask Mizuko memorial service to the temple, but it does not necessarily mean that you must do so.
The best way of Mizuko memorial service is to “do it at home by yourself”.
For the one who has Mizuko, but it wasn’t in state that you could consider such matter, so you have been excluding it from yourself, I would say you have better to give Mizuko memorial service at home by yourself. It is not too late now.
Memorial service method at home
It does not take big cost because you do it yourself. If you do not want to be known by your family, you can give enough service where you determine "your own memorial service object" instead of Jizo stature.
You can place such your own object casually in living room or on your desk and talk to it familiarly and gently any time.