Gender reveal question...

Krystina
So my husband and I find out the sex on the 20th of April, we have decided we want to do a gender reveal party to announce the gender to family and friends all at once, well, the weekend following the 20th is our one year anniversary so we don't want to have the gender reveal that weekend, not to mention we fly out of country that Tuesday for our anniversary. We chose to do it the first weekend we got back from our vacation which puts us at may 9th. We talked to my husbands parents tonight about it and they were so upset with us that we wouldn't tell them before hand and they felt they had the right to know first because they were the grandparents. We explained to them that we wanted them to be the ones to open the box of balloons at the gender reveal to see their reactions and wanted the group of friends there to help share the excitement. My mother in law flat out told me she was not going to be apart of that and wanted to know the same day we found out..... Anyone's thoughts or similar experiences? My husband and I were completely caught off guard, we feel it is our choice to tell people when we are ready to tell them and there is nothing wrong with us keeping it to ourselves for a bit.... Thoughts????