I have tried everything, especially as most of the blankets we own are not twin sized. We've had the added difficulty of putting a too-large blanket on a bed & all 3 of them hate a top sheet. I'm not sure why, they all like being in my bed w/ it's top sheet. I generally just fold the top sheet in half on top of the plastic mattress cover & cover it w/ the fitted sheet to put an extra layer underneath. Sleeping on only the fitted sheet over the plastic makes for a sweaty night.
In the colder months I just had them fold the comfortors in half like a sleeping bag, it's easier to make that way. But when the inevetible night accident occurs it's incredibly difficult to wash & nigh impossible to wring. I can, but it's a herculean effort & puts the scheduled laundry on hold, especially as that is not laundry I let hang around more than a day.
I went online to see how other parents handled this & found something called a bedcap. It's basically a fitted comforter w/out all of the overhang. I was pretty disheartened when I saw the average price was $110.00 for a single set of bedding. I already had a ton of bedding so I figured I'd just try my hand at it myself.
Here's the original blanket, for a double bed. Their mattresses are "bunkies" which I think is the same size as twin but much thinner.
Measure your mattress. I disremember but I think this was a 11x14 rectangle.
Remove some fluff to facilitate ease on your machine.
I had to go back & cut about a 4" strip up either side to get rid of too much overhang. Do that before you pin your square.
I just used a zig-zag all the way around.
A new box seam!
I didn't have it on the bed but this was how I was having them fold the too large blanket on the bed in the morning during make-up. W/ one end boxed, it really makes folding/ storage of the blanket easier & neater
The completed & made bed. It's actually too hot for these comforters now, she just sleeps w/ a light pink baby blanket at night.
A view of the newly boxed in end. There you go! You've just saved your family $100.00 & made the mornings more peaceful w/ happier & proud children.