Occasionally, as a young rabbit grows, the cartilage doesn't stiffen enough to keep pace with the rapid growth, and one or both ears fall for up to a month or two. Often they will go up and down depending on heat, humidty, etc.
My young Palomino turned into a lop for several months when he was growing quickly.His earsare now very firmly upright, but it was pretty cute while it lasted. His father's ears drooped just at the tips when he was young, during the hot weather in July and August.
A young true lop's ears will go down and stay down,but yes--airplane ears are common in both purebred lopsand crossbreeds, so you can get a rabbit with one uppie and one downie.
Most young lops' ears will be down by five or six weeks old. If Miffy is older than that, it may be just a temporary growth thing. My Pal's ears went down when he was, oh, three months old or so.
Either way, no big deal--she'll be fine, and totally adorable.
Rose
EDIT: her size and body shape and fur type are consistent with a four to six week old baby, so it would be just the right time for her to lop if she's going to.
