best friend's baby shower gift?

My best friend's girlfriend is having their baby soon so they're throwing a cute little baby shower.
The baby wasnt planned at all it was more like a one night stand but he obviously wanted her to have the baby and he like loves rock music and stuff like that and she's the complete opposite she loves everything pink and makeup and so on.
Now I dont know what to get the baby and I dont have too much money either because I'm going to college and it's the first time I'm on a baby shower but he's like my brother the baby is my niece I need something personal and cute but I'm so uncreative...
He's a musician (in a band) and just earns a lot and that girl is pretty wealthy too so coming to their baby shower with diapers would be kinda embarrassing I guess.
He's not a materialistc guy at all but I dont want to look so pathetic next to all their friends and family..