Millie Bobby Brown and Jake Bongiovi On Stroll With Baby in The Hamptons

Millie Bobby Brown and hubby Jake Bongiovi just revealed they adopted a baby girl this summer — and TMZ’s got the shot of them already deep in parent mode.

Check it out — Millie and Jake traded red carpets for diaper duty in the Hamptons on Tuesday … pushing a stroller and soaking up the East Coast rays like full-blown parent pros.

No Hollywood glitz here — just Millie and Jake, dressed down and strolling the streets with their baby girl … soaking up the simple joys of parenthood, just the two of them.

Looks like they were savoring their final quiet days as a trio … before dropping their adoption bombshell on the world.

The 21-year-old “Stranger Things” star has never hidden her dream of being a young mom — and now she’s making it a reality … kicking off what she hopes will be a big family, just like the ones she and Jake grew up in.