Can you get your SD and SS together with your parents and PIL and do dinner?
Tell them all there and then and then use FB or SMS to tell other ppl?

We called our parents with DD1 as mine are 2hrs away and i thought it only fair if mine find out like that then so should his... we got in trouble from my MIL... lol

my SIL bought little pair of socks that said i love nanna and i love poppy and gave them to her parents at tea one day, my MIL cried for hours!