Jeez, some of you ladies had a really hard time with this! I told my family and DH's family last week (at 12 weeks). My family were great, very excited. SIL *****ed about how she had a right to know earlier, but was ambivalent about the actual news, and MIL has been droning on ever since about how it's understandable that my SIL is upset, since she was left out.
Truly, I'm missing that excited little feeling I had when only me and DH knew. Since when did our pregnancy become the property of my in-laws, and do other family members really have 'rights' in these situations? It's not like my SIL would ever consider babysitting, or helping out in any way once the baby is born, even if I begged her to.
To be honest though, after reading some of these stories I can see just how much I need to build a bridge over this.