4 year old’s right eye goes cross-sided ?

Last night I noticed that my daughters right eye goes cross eyed sometimes. Maybe when she is focusing too hard ? She snaps out of it and it seems like she is aware of what she’s doing. Its happened when I’m taking a picture of her, when she’s watching tv or I’m talking to her and she’s just staring at me. Has anyone experienced this? She had her eye exam done months ago and 100% passed it. Just concerned of what exactly it is. I will bring it up to her pediatrician but just wanted to see if anyone has experienced this.