Fabric for a costume

Hi! First time posting in this forum.

My Mom taught my sisters and me how to sew. It was considered essential, especially for making otherwise-expensive dresses of the sort you would only wear once, like a wedding gown or prom dress, or wouldn't wear often, like piano recital dresses. When we were kids, she also sewed us matching nightgowns, beautiful wool kilts and coats, dresses, and Halloween costumes.

When my daughter was little, I tried to continue the tradition. I sewed her "layette," and later a preschool wardrobe in all purple and pink, then a Halloween costume: the classic clown costume that seems to have been around since the 1950s! Size 2 turned out to be enormous on her. The next year, same costume - still big on her. I think she was 5 or 6 and still when Halloween came around she said, "Let's get out the clown costume!" not knowing she'd finally outgrown it.

This year, I have a granddaughter!! She'll be 6 months old in October. In a baby shower game, my daughter said the baby's first costume would surely be a bunny. So after not sewing for years (and knowing it might be the last thing I sew), I want to make her a bunny costume.

I bought Simplicity pattern #9331. It mentions cotton and 'satin types,' and something about pile. I'd love to buy the fabric online not only for selection and frugality, but also because I have broken my ankle and it's difficult to crutch around -- don't know if fabric stores have the motorized wheelchair carts.

The real 'rabbit fur' looking fabrics look too unwieldy to work with for sewing an infant's costume. I'd like something nicer than basic jersey fleece. Some online shops advertise a "minky" fabric. What is that?? Any suggestions would be appreciated!! Thanks!