Have you considered making an appointment with a therapist (ideally one who deals with teens) yourself and seeing what a professional says about whether this baby thing is okay or does need intervention on? At least you would have some support or might feel better.

I think he's just telling you he needs some more attention.
point blank period because he knows it's not typical for a 17 year old to do these things. He just wants you to notice him. Dad do you work a lot? That may be the problem.

Wow - not intending to minimize your suffering - but this sounds like something out of a movie. I have been through hell & back with my teens. To think I had a problem when their wearing pajamas to school became a fad... Then they were on drugs and wearing baby binky necklaces and sucking on them - like all the kids were doing that a few years ago.

You haven't mentioned drugs - is it a possibility? Are attention seeking & shock value a possibility? Kids do weird things to rebel... My daughter rebelled my rainbow hippy ways by wearing all black, dying her blonde hair black, listening to black metal & wearing inverted pentagrams ughh .

My kids also have mental health issues like me - bipolar mainly. If I were you, I'd be worried, I'm a worrier. Idk if I'd run him to doctors or play along like I'm not shocked coddle him make him only allowed to watch Winnie the Pooh set strict nap & bedtimes canned baby food only and hope he gets this attention he needs & finds a new interest.... ??