Unexpected pregnancy after vasectomy

My husband had a vasectomy 9 years ago. We went and had his sperm tested twice after the procedure and he was confirmed to be sterile. They did warn us that recanalization could occur but it was much less likely to happen after the 4 month mark. Welllllll. Here we are 9 years later and not only am I pregnant but I'm pregnant with twins! A huge shock but a blessing nonetheless. So we are really restarting. We have a 9 year old son(vasectomy was done while I was pregnant with him), 11 year old daughter and a 15 year old daughter. We haven't told the kids yet. I'm 22 weeks with a boy and a girl and all tests have come back normal, I just don't know how the kids will feel