I'm sharing my most useful crochet pattern today! If you have been to my house, you've seen our yarny doorknob covers. We much prefer them to the plastic ones you can buy in the baby safety section of BabiesRUs, Target, etc. I practically guarantee that no child under the age of three will be able to defeat these. If your kiddo is older than that, it depends on your child's ingenuity. My tall, strong, destructive 3.5 year old is helpless against the crocheted doorknob cover. He can crack the plastic ones off doors in no time flat. Try it!
small amount of worsted weight yarn (I usually grab some random acrylic from my stash)
size H crochet hook
row 1: ch3, 12 dc in 3rd chain from hook, join with sl st in first dc, ch 2, turn (12 stitches)
row 2: 2 dc in each stitch around, join, ch 2, turn (24 stitches)
row 3: *2 dc in first stitch, 1 dc in second stitch* repeat *to* around, join, ch 2, turn (36 stitches)
rows 4-5: 1 dc in each stitch around, join, ch 2, turn (36 stitches)
row 6: decrease to 18 stitches by dc2tog all the way around , join, ch 2, turn (18 stitches)
row 7-8: 1 dc in each stitch around, join, fasten off yarn, weave in ends. (18 stitches)
cut a length of yarn about 12 inches long and weave it in and out through the stitches of row 7. stick it on a doorknob and tie a TIGHT knot in the length of yarn. trim yarn ends, and voila!
Your doorknob cover will fit loosely on the doorknob. That's the idea. A toddler does not have the strength to squeeze the cover against the doorknob hard enough to create enough friction to get it to turn--that's why they work!
If you try it, let me know! I'd love to know how the pattern worked out for you.