I love the idea of it being a comic, and something that's not usual, but i think a baby isn't exactly 'fear' it's inconvenient... i just think people wouldn't get it, a boggart should be something that terrifies us, and if we are off to try to help the baby etc... it just doesn't sit right with me
just a few ideas for silly squid fears:
-a barbecue (fried calamari)
-A one legged animal (Oh god, look how FEW LEGS it has! it's disgusting, look how it moves! - a parody of spiders being scary because they have so many legs)
that's all i have for now... i love the idea of a comic