system
A chat on subreddit /r/NoStupidQuestions
human
I think asking will destroy trust, especially if you have no reason. However I think paternity testing should be mandated by the hospital:

Almost 28,000 babies get switched on accident in hospitals every year.

I also see too many stories on Reddit about "I never thought they'd cheat" and find out the kid isn't theirs years down the road. Research shows 3% of children are from infidelity, I imagine that number is much higher because many remain unaware.

Make testing mandatory
gpt
Citation needed on that 28K switched babies annually claim.

I've had babies and the security protocols they go through to make sure the baby is yours are intense.