Help with small wrist warmers...length?

I’m making wrist warmers for an almost 8 yr old girl’s birthday on the 26th. I have the width right I’m sure but I can’t decide how long they should be. I’ve looked at all the free patterns I could find but nothing has helped.

I’m knitting them flat with a k2/p2 ribbing pattern & plan to stitch them leaving the thumb hole open. If I have time I might go back & pick up stitches to add open thumbs.

I’m using Baby Bee Lambie Pie ombre (baby camo) yarn for a decorative edging. The main body is a solid green Red Heart Soft to match. I’ve CO 34 stitches with a US sz. 6 needle.
They’re looking really cute but I don’t know where to stop. Help!

I can’t imagine that an 8-year-old’s wrist is more than about 4 inches, if that, and you have to allow for some stretch.

Maybe look at some children’s mitten patterns to see how big the cuff is around.

they ended up 5 1/2 inches long. I had my grandson try them on to know where to leave an opening for the thumb. She’s the same size he is. Then, I made a scrunchie for her hair. I’ve got time & yarn enough to make her a matching hat.
This has been so much fun. (((HUGS)))Verna
I finished the hat - kind of a modified beret I made up as I knit & had yarn left so I made a narrow scarf to complete the set. She opened them this afternoon, put the pieces on as she came to them, everything fit & looked great. She loved them & her family all went on and on about them. Several Aunts wanted to know where I bought them then, would I make them for sale? It was a nice feeling.