help please

My sisters husband wants to get the family to get together for her b-day at a restaurant. However they don't have the money to pay for it. Her DH has asked me how does he word this to our family that we are all going dutch with out embarrassing himself. he want to do this in an email

Re: help please

i would write that it is so and so b-day and i am taking her to this reasurant if anyone is interested in joining us the approx. cost is $$-$$ per person.