Best way to explain that Daddy is now shared

[Lasvegas]

My DD is 2.3 she has never met her bio dad. My partner has 2 DS 8 & 6 who he sees frequently but for reasons of geoography neither myself or DD see them often. The 3 kids 'talk' on the phone and we talk about what the others are doing etc etc. DD now calls her 'step dad' Daddy, this was discussed with the sons and they were fine with it. But they have not yet been faced with hearing another person call their father Daddy and I suspect this will be crunch time, for he's mine not yours etc. Over Easter we will all be together, any general advise on how to handle potential problems?

No real direct experience of this LasVegas but I was worried about similar things when my dd1 was born as my (ex)p had 2 dds from previous marriage who were 10 and 8 then. I thought they might be a bit jealous of a baby who spent more time with their Dad than they did. But they adored her and there were no problems at all. Not quite the same because they were (half) sisters but hopefully you won't have any problems. Try and make sure everyone is included and plan some fun days out or something so there are distractions going on.