Baby lifts her right arm higher

My daughter uses her right arm/hand for almost everything . She does use her left hand & arm but I can tell her right arm /hand is more dominant she will Be going in for a Eeg next week if they don’t cancel her appointment because of the covid19 :( I will have her sitting in the swing & she reaches with both arms but her right arm is always higher above her head !! Anyone else experience this She is 6 months