try to spray with aerosol hairspray it work to remove feltpen marks from walls good luck

You could try a mixture of bi-carbonate soda and lemon juice made into a paste and spread onto the ink marks and just leave it for several days then rinse off and repeat if necessary, be aware though that the lemon juice may act like a bleach and could actually bleach the fabric.
Alternatively you could just mix the bi-carb soda with water or if you have no bi-carb soda you could use bottled soda water.

There is also an acne treatment cream that works really well for removing permanent markers, inks etc. from all sorts of things, even leather, vinyl and plastic. It contains 2% - 2.5% benzoyl peroxide and you just apply it and leave it on the article, preferably in the sun for several days, checking it by removing a small section and re-applying as necessary. You should Google "acne cream with benzoyl peroxide" to find the brand name marketing this product in your country. This works so well I always keep a tube on hand for when I get biro on my handbags. :-)
Hope this helps. Hugs n roses, Meganne

I used hairspray and then blot with paper towel. It worked pretty well but it does take quite a bit of time. Good Luck (and hide the markers).

`12No ideas, but prayer! Will see if that helps you.

Do you have the offending pen? If so, use it on a scrap of fabric and try washing it. If it is a pen intended for children it should be washable. If the little darling got his hands on a permanent marker and meths doesn't work you have a problem! (Meths won't remove a water soluble dye.)

My daughter washed and dried micro fiber sheets that a ball-point ink pen had leaked all over them. Mom to the rescue.... I love my Oxi-Clean. I use the powdered one found in the laundry aisle. I filled my machine with hot water and the oxi-Clean and soaked them overnight. the sheets came out just like new. This product does not bleach out colors.

I absolutely swear by Oci-Clean. It removed stains from an inherited antique lace tablecloth that were years old. Soaked twice overnight and all removed.

Soak cotton ball with rubbing alcohol and press on ink spot and absorb the ink spot with a cotton ball in the back of item or use a paper towel to absorb the ink in backl. Keep using new cotton balls and or paper towels. I have gotten many ink stains out this way. The hairspray suggested by someone else has worked for me too. If this doesn't work try rubbing the stain with a bar of white soap and rinsing with warm water, repeat a number of times till the ink is gone.

Well?

I am a firm believer and user of milk to remove ink stains. And I have done some beauties in my time. That is: pen all over my best work suits; a lap full of ink while doing calligraphy when the pen broke. Texta stripes on my belly errr, the clothes.
I fill an 8 inch glass pie dish with milk (shallow dish) place soiled part of garment in the milk and gently run fingers over fabric to soak the milk in. Refresh quantity of milk as needed. Remove garment when ink stuff is gone. Wash normally to remove milk.
please note: always place the pie dish on a surface where is will not be disturbed and where is milk leaks over the edge, it won't hurt anything.

Hair Spray and an old toothbrush, it may work

nail varnish remover just may do the trick I have used it myself and it worked ok

Oh dear. I am afraid that I do not have a remedy for you Caroline. Some amazing answers here. Let us know how it goes.

Have you tried 'lighter fluid'? It worked for me on a permanent black magic marker stain on an Oxford cloth shirt...cream colored. Hand wash this out with cold water before you fully launder.

The water based kids markers should just wash out using your usual detergent or powder.

ok have you managed to get the marks out of the jumper yet