My cousin names her baby this name also.. Not sure whether this name is unpopular, but not common for this generation. I personally like this name, the meaning is just like what commented by Alex (another user).. Btw, I have "念" in my name also.. That's why I like this 😊
念means think, thought, 慈means kind, love. This name is also a character appeared in Jin Yong 金庸 novels 射雕英雄传and 神雕侠侣，mother of Yang Guo 杨过。
thanks much