Gypsy Rose Blanchard's making it clear ... she's carrying Ken Urker's baby and no one else's -- even as fans openly question the timeline on social media.
GRB sat down for an interview with "Good Morning America" Friday ... and, she doubled down on the paternity of her child, saying it's definitely Ken's baby 'cause she and estranged hubby Ryan Anderson stopped being intimate way back in March.
Check out the clip ... Gypsy reiterates her timeline, saying she left Ryan in mid-March -- so she's 100% sure the baby's Ken's.
Blanchard adds she's more focused on taking her prenatal vitamins, drinking enough water and staying healthy for the baby she's carrying ... though she adds she hopes Ryan's doing alright emotionally.
Gypsy already shared her sex timeline with Ken online BTW ... explaining in a TikTok comment Wednesday that she "Left Ryan March 23, had a period April 17, made love with Ken and only him April 27, 28, 29, 30, conceived on May 4 and positive test on May 24."
Still, some fans are doing the math and saying it doesn't totally add up ... though, if you count 40 weeks from when Gypsy says she conceived, it essentially works within the timeline she's suggesting.
Either way, the rumors are going to be put to bed soon enough ... 'cause Gypsy and Ken need to perform a paternity test anyway. Like we told you, a strange Louisiana law means Ryan's the legally presumed father until Gypsy proves otherwise.
But, clearly no doubt in Gypsy's mind ... she's sure Ryan Anderson is NOT the father.
We covered the drama on the latest episode of TMZ Verified, available on all podcast platforms.