The reason of why his hair changed color is uncertain.

"Of course your hair will change color to match," she said, hoping it was so.

His hair was going to be dark orange, but later changed to regular brown.

The hair was changing too, going from dark brown to crystalline black.

Johnny's hair has noticeably changed from black to brown in the new season.

For a moment only, it seemed to him that her hair had changed colour.

For a second I thought his hair would change.

The hairs around had changed from deep purple to red again.

Her hair, once a dark blonde, had changed in those years to a medium brown.

You can be sure the mother's hair will change color and length a dozen times in the next year.