How would you answer this question from step child

[AreWeThereYettt]

Me and DP are getting married and his DS asked me the other day why mummy isn't invited.

He got distracted before I answered.

How would you answer this?

DP and his ex co parent well but they aren't overly friendly and they don't really like each other outside of talking about DS.

I get on with her okay, no dramas or anything but nothing more then a chat at drop off/pick up kind of thing.

If my DP ever asks me to marry him, I wouldn't invite our ex's, we have family and friends so the kids would be fine and we don't get on well with the ex's. I fully expect my ex would invite me as free childcare but I would refuse- it's about time his family stepped up.

Ohnooonotagain, if you would like to marry your DP, ask him! (I realise I am entirely missing the point of the thread here - sorry).

Aww thanks @tinyvulture XXX

He knows I'd marry him in a heartbeat. We're totally both in for making this lifelong, but he's taking a little time to come round to marriage. I'm happy to wait for him. His first marriage was not for the right reasons and there's no way I'd want him to feel he has to marry me to make me happy- it has to be completely right in his mind.