What can I do for this chair?

[AngeloMysterioso]

I’ve recently been given a secondhand Stokke Tripp Trapp chair. I’m planning to sand and paint the frame so it will match my dining table chairs, but does anyone know what I can do about the bits where the wood has been chewed up?

Fill with wood filler and sand. It won’t show as you are painting it anyway.

I’m not painting the shelf parts- would I have to sand, fill and re-varnish?

Yes, but unless your filler is a perfect match you'll see the repair.

So what else can I try?

You could just try rubbing it down/sanding it and see what it looks like. It might be ok. If not then painting it is probably the only option.

Sand , fill and revarnish, but it will never look new again.
I would give it a good clean, sand entire surface lightly and paint.
My dd did this on same piece and it turned out perfectly fine. She used a medium grey acrylic paint.