My friend has a brother who had autism, he seems pretty normal to me though, autistic kids dn't show emtion

but the hamsters or something died and he was cryin, like he was really upset and things like jokes he laughs truely, he has a little brother who is 3, he's great with him, if he cuts his knee, he'd b right downat his level, tellin it's ok, moms gonna b here soon, gettin a big hug, thouggh he other shows, i mean i don't have any proof, but i just odn't feel that he has any love 4 his parents or anyone, that's when i feel the autism in him, has he got it mild? or is autism just autism