Blue tits

A blue tit roosts in this bird box every night, but today there was action during the day.  I noticed on the box cam that a bird was sitting inside without moving. I went to the window to look at the box, and spied a bird sitting outside the box.  A bit later, I had a look at the recorded images from the box cam, and found that there had been a bit of a fight. I don't think any harm came to either bird - they both were seen outside the box afterwards.  And now the bird is at its usual roosting spot.