I honestly doubt she was boosted. I think she said it to be like “see I did everything right”. Over 30s could only register for a booster from 29th December and you can’t get a booster if you have had covid in the past three months (several people asked me this when I was getting mine). So either she got it before Christmas and before she was infected, or she’s lying. Not sure how she would have got it before Christmas cause they were prioritising over 60s but then again she probably held an elderly person down just to get it. Nothing would surprise me