To think that a MNer would know how fix this?

[shescreamsforme]

I sewed a romper for DD but didn't finish it before she out grew it 🙄 so I passed it on to SIL. SIL put it on DN and got some lovely photos... then she washed it and the buttons have stained the white fabric 🤦‍♀️

Any ideas how to make it white again?

Bleach?

Dye it a deep red, or remove the buttons and attempt stain removal.

Paint bleach on with brush, leave a few minutes then wash in the machine. All will be good as new

But maybe replace the buttons before you wash!

Remove the buttons. They are the problem by the looks of it.
I am not convinced by bleach. Lost clothing before to this method. They turn yellow.
I would try dying it a darker colour.

Maybe try taking the buttons off then soaking it in a bucket of Ajax in water. You can also wash it on a hot temperature with ecobleach for washing machines.
I had a lace tablecloth that was mould stained when our boiler leaked into the towel cupboard (gradual leak we didn’t notice for weeks). I left it in bleach water for a week or so, come up as good as new.

Take the buttons off.

Get a tub of vanish oxy white powder stuff. Put some in a bowl with warm water and leave it to soak for a good few hours. Then wash normally. Could even make the powder into a paste and rub on the stains direct before soaking.

This method has worked a number of times when I’ve had different stains on white shirts, dresses etc

Definitely remove the buttons, then I'd try Ace for Whites laundry bleach.

Plain white cheap toothpaste, rub it onto the stains then leave in cold water overnight, was as normal.