Best Friends Broken! Millie & Maddie's Movie Mess

From secrets to lip gloss, teenage girls share everything — except the limelight. RadarOnline.com learned exclusively that's the case for Stranger Things star Millie Bobby Brown and her BFF, Dance Moms breakout Maddie Ziegler, who are at odds over Brown's upcoming movie, the big-budget Enola Holmes franchise.

Brown, 14, is producing and starring in the flicks — which are tipped to be the next Harry Potter — and Ziegler, 15, is begging her bestie for a role.

"It's a huge opportunity for whoever gets cast alongside Millie," explains an insider. "But Millie doesn't want to work with anyone she knows, not even her best friend."

And on a scale of one to 10, Ziegler's hurt is at an Eleven, a source told RadarOnline.com.

"Millie is being very matter of fact about this, but that's probably why Maddie is upset," shrugs the source. "She thinks the fame has gone to Millie's head and hopes she snaps out of it."

As RadarOnline.com has reported, Brown's career is just starting to skyrocket, and will reportedly make a whopping $350 thousand per episode for season three of Stranger Things.

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