Sometimes people with Down Syndrome might stick out their tongue. This could be because of a small mouth, slightly larger tongue or, most likely, low muscle tone in the mouth (hypotonia) or sometimes to help them breathe more easily. Speech therapy can help people with Down Syndrome overcome this... BUT we can still stick our tongue out at you if necessary.
Frida’s tongue does poke out when she is relaxed and sleeping. It looks like a combination of her having a smaller mouth and lower muscle tone. It also pokes out a lot and flickers quite aggressively (and alarmingly quickly) when she is demanding food! Luckily, her ability to feed does not appear to be at all impeded by whatever it is causing it. The advice I have read is to poke it back in when she’s resting to encourage her to do this of her own accord as she grows up. Not for any other reason other than to encourage proper breathing so she doesn’t just rely on her nose!