Preggo halloween costume ideas!

So this might be a special case -

My little brother (20) has down's syndrome. Every year for halloween, I take him to our downtown district where they shut down the streets to do trick or treating at the shops and lots of fun events. He LOVES halloween and dressing up, and always looks forward to going with me.

Dilemma - I'm pregnant. Like, third trimester pregnant. My husband will have to work that night, so he cannot join us.

My brother and I usually do "couples" costumes so we can easily find each other in case of any problem/emergency or crazy crowds. All couples costumes that include a pregnant woman are either sex related (like "hey i did that" 😂😳) or too boring/obscure for his taste.

Anyone have any cool ideas for what we could dress up as this year??? I'm open to almost anything!

He loves mainstream cartoons/characters and isn't too fond of horror/gory stuff. He can't do masks, but wigs and hats are fine!