My cat knew before I did - and this started around 11/12 dpo. He likes to 'incubate' me and is extra loving. Although he also started suffering anxiety when I'm not there causing bladder problems which has cost us a lot of money.
He's going to be so disappointed when a tiny human pops out rather than a litter of kittens!!
My younger cat was a kitten when I got pregnant with DS - she knew. She'd sniff my belly and spent my entire pregnancy on my bump. She's now a massive lump of a cat and is doing the same with my second pregnancy.
Our 13-year old cat Baldrick started lying across my stomach ever since we started TTC in the summer. And now he'll just sit there, either next to me, on me or at least 'minding' me. I always joke he's going to sleep in the cot with it if it depends on him. lol