Motherhood or sisterhood? Ever since Ashley Olsen wed artist Louis Eisner in December and gave birth to their son, Otto, the 37-year-old is too busy for twin sis Mary-Kate Olsen — and MK is hurt!

“She still expects Ashley to be the same as she always was,” an insider tells In Touch. “She’s really struggling to accept this new version of her sister.” The insider adds that MK is beginning to resent her brother-in-law for coming between the once-inseparable sibs. “It makes sense that she’d blame Louis because he’s the one putting his foot down and letting her know the boundaries.”

At the same time, Ashley — who still works with Mary-Kate at The Row — is going through some growing pains as well. “It’s tough on her, she hates upsetting her sister,” says the insider. But now that she’s a mom, her first priority is her son and she and Louis have made their own little family.” All of which leaves Mary-Kate feeling left out in the cold. “The sad truth is, things have changed.”

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