Ow ow ow separated abdomen?

I am on the last leg of my second pregnancy and something has happened this time that didn't before. From what info I have gathered from the internet my abdomen muscles are separating. Feels like a bruised burning feeling right on my stomach muscles and when I lay on my back and lift my head and shoulders there is a ridge down the middle of my stomach. Have any of you ladies had this? Does it take extra care and work to get back to "normal"?