Son (11) doesn't play with his sister (9) anymore

To put things into perspective, I'm a single father (35) of two kids. Their mother is out of the picture, so it's usually just us. Since a few days, almost a week before the start of this new "outbreak", my son begun distancing a bit from his sister. They have always been the kind to do everything together; play games, watch movies, swimming, etc. Even at school I know they sometimes spend time together during breaks.​Cut to a few days ago, and I start to notice some different patterns. First was one day after we all arrived home, I was going to watch some TV and my daughter invited her brother to watch a movie to her room. He said that he would go later, but I noticed he never came out of his room until dinner that night. Situations like this where she would ask him to do things together but he declined kept arising, and I started to get worried if something could have happened. My daughter looks heartbroken, she doesn't understand if she did something wrong to make him angry. And when I try to talk with my son he either avoids the issue or says that everything is fine.​Nowadays, for obvious reasons we are spending a lot more time at home, and living like this has become impossible, with it being evident that for some reason he is avoiding her. I don't want to force anything, I just want them to get along again, like they always did. via /r/Parenting https://ift.tt/2ygzUn8