Baby's hair

My son's hair looks unruly. He's got plenty of hair on the top of his head, but a lot of it has fallen off in the back. He's three months old. I don't mind his hair looking the way it does, but it seems to bother my mom when we go out in public. Is there a safe product I can use to style his hair? I've heard lotion is ok to use. Any advice is appreciate it.