hi to all parents
ı have 2 babies my son Kirpi and babygirl vişne

Kirpi is now 1 year old.3 months ago his left ear fell down ı asked to the veterinary he said 'some of thems ear up some of thems down'.and 1 month ago hıs right ear fell down.he dont have any ear infections ,showed him several vets.is it normal? if its not is there any ear exercise to make them up?Vişne is 5 months old and her ears always up even when she sleeps.ı love him with his every look just want to be sure if he is ok.
thanks