Are there any super heroes he likes? Bedding i tones that work with lavender (purpl) like Batman. or Paw Patrol, etc. would change the vibe. His stuffies and books on the shelves would also make a difference. Mabe a dark chair instead of the white one. My 13 year old grandson also likes purple and his room has orange accents.

I would leave the white built ins.

Introduce Denim into the space. PotteryBarnTeen has some nice chambray and Denim bedding, drapery panels.

There is nothing effeminate about various shades of purple. He is a young child, so he is not yet trained into any limited thinking about colors. All he knows - is that he likes purple! So just do various shades of purple in the room, in bedding, etc. - and call it a day. If you want to be fancy, bring in some paisley print with some purple in it. Paisley works for grown men, too.

Agree with suggestions so far. Leave the white, change the desk chair. If seller leaves the chair, paint it purple. The navy bed will be great with the paint color which reads lavender to me - add ’real’ purple accents with area rug etc.

Ahhh, Prince. Made me smile, Freedom. :)

I’d consider painting the built-ins navy. Not because it reads boy or girl, I just like blue and purple together, and you said his bed is navy. I think it would look so much more interesting than all that stark white.

Or purple … the wall color or a darker purple:

I always like the look of built-ins (if not wood) that blend into the walls or are a similar color. Think of it this way — if you were buying bookcases for the room, you wouldn’t buy them in white, right? So why not change these? They aren’t precious.

Paint and add some fun hardware.

I like the idea of the wallpaper on the backs of the cabinets. You could easily add blues, yellows or grays into this room as well.

I'm wearing a shirt just in that color and my favorite pairing is navy.

So, thumbs up for the bed.

I'm really liking this:

https://www.walmart.com/ip/Your-Zone-Dino-Roam-Bed-in-a-Bag-Bedding-Set-w-Reversible-Comforter/46142994?wmlspartner=wlpa&selectedSellerId=0

I think the gray Triceratops would play off the light purple walls.

Add some dinosaurs on the shelves, a couple of prints on the walls, navy chair . . .

one advantage of the peel-stick wallpaper is that it is removable, so if this year's big fascination is reptilles, next year's can be soccer balls.

I think plum would look very sophisticated if you don't go navy.

I love this purple peel and stick backing for the bookcase that mytwo cents posted. Here are some ideas for pillows and a chair from Walmart and Wayfair.

I would not touch the builtins but the bedding is the easy way to find something less girly and by the time heputs his stuff in the built ins it will look very different. I would do some bedding like this and maybe some really cool decals but honestly he will have a totally differnt color he loves next year so just wait and paint the new fave color or just paint now and IMO a really neutral color for the walls and the accents and bedding in the fave color of the year.

Thanks, everyone, for all the great ideas! You've given me a lot to think about.