Need help wording an invitation
Next month will be my Mother's 70th birthday and her husband's 75th. They want to have a combined birthday party at their home for between 30 to 50 people. The plan is to have a "come and go" event, about 4 hours long, so that people coming from out of town won't feel rushed to get there, and everyone won't all be crowded in at once. We plan on serving finger foods, (sandwiches, veggie and fruit trays) and cake with ice cream. They don't want any gifts.
It's easy enough to write "no gifts, please", but is it tacky to ask that if they can't attend to send a card? There are several people who live out of state who in all likelihood will not be able to attend. These are people that are important to them, and I know they would love to hear from them even if they can't be there in person. If they can't attend, we're thinking about having all the cards sent to one place before hand and then letting the honorees open them at the party. Does this sound like a good idea, and can someone please help me with the wording?