I didn't read the replies, but I am sure people said it can be just a normal, developmental issue. It certainly can!
Here are some other thoughts:
Try keeping a food diary- sometimes allergies can cause bed-wetting (it could be something environmental too- shampoo, bubble bath, exposure to bug spray or a scented candle, etc.)
It could be strep. My daughter wets the bed when she has strep throat. I know it's weird, but true! We went through this for YEARS before I figured it out. Sometimes my daughter comes back negative on the rapid test they do in the office, so be sure to have them do a "culture" where they check it after 72 hours.
A UTI- this was probably mentioned, but it wouldn't hurt to have her checked for a urinary infection.
Could it be psychological? Even good things/excitement can be stressful to kids. Someone described stress to me as "filling a bucket." Let's say she goes to a birthday party, then you and your hubby have a little argument in front of her, and then isdisappointed because herballoon from the party pops..... seems like nothing much for us, as adults, but if you look at it overall from her perspective, it's a FULL bucket! If you think it might be this, try doing a "feelings check-in" at night, where the two of you sit together for a few minutes and talk about the day, or she draws a picture or writes a few words. (I find this helps my kids sleep better overall, anyway!)
Something you might do to save yourself some sanity is make the bed in layers... put on a waterproof pad, then make with bottom sheet and top sheet, THEN put on ANOTHER waterproof pad and make AGAIN on top of that. Then if she wets in the night, you peel off the top layers and already have another made bed underneath. You still have to wash the sheets, but it saves you the hassle of making it again immediately.
Hope this helps,
M.