Teddy wasn't sneaking, exactly. Sneaking meant he didn't have permission to go around the ship. And if you didn't ask, then you didn't get told no. And if you didn't get told no, then that meant you were totally allowed.
Kind of.
He was walking through the halls, not exactly disguising himself, and he was pretty sure space didn't have tiny bugs but you couldn't be too sure. But then the tiny bug turned into a full grown almost-teenager and that meant it was Pym! "Hi!" He glanced around, making sure Julia wasn't around. Just in case. Not that he wasn't allowed out and about. It wasn't his fault the Entity had decided they didn't technically share a house anymore. "Of course I do!" Because why wouldn't he want to explore, well, anything?