Any mummies encounter such issues that babies sleep so sweet and suddenly cried so loud and difficult to coax and put LO back to sleep? Currently day time is taken care by my Mil as I'm back to work... LO is currently in 7th month old... yesterday my Mil brought my LO to Rc or cc for her singing session then at night 10+ come back....

Yes I have once encountered it with my boy. We brought him out and he didn't have proper sleep during the day. He cried non stop refusing to open his eyes too tired in the middle of the night. He cried badly and scratched my arm. I brought him out to the living room. Assuring him that I am there and we are at home. Ask him to open his eye and see. I kept assuring him that is OK. I am with him. After that he calmed down and opened his eyes.