Vintage button down long sleeve children’s blazer/jacket circa 1970. Size 5

Vintage circa 1970 children’s multicolor plaid blazer, colors are Navy/Yellow/Red/White. Excellent condition, from personal collection rarely worn. There is one small stain on the cuff, not noticable. There are no tags, but it seems to be a cotton mix. I am not sure of the size, please see measurements below. Length: 17.5 inches Width: 12.5 inches Shoulder: 10 inches