Toddler party dilemma

[GP75]

My 4 year old twins have just started a new nursery and one has received a party invite but not the other. I'm assuming it must be a full class party as we don't know anyone and the twins have no friends and we don't know the birthday child. So it's probably an oversight twin 2 wasn't also invited. I can't take one and not the other, at this age twin 1 would refuse to go and twin 2 would be a nightmare. What do I do, just decline the invite, ask if she meant to invite twin 2, I wouldn't even know what to say 🤷‍♀️

I'd contact the mother and say Twin 1 would love to go but you'll need to bring Twin 2 as you've no other child care, the mother will likely say both were supposed to be invited

Tactful message to the organiser.It's probably an oversight.