was seen at family-focused events surrounding the Little Couple; son of Bill Klein and Jennifer Arnold is described in public mentions as their child William Rijin Klein, with titles around family life and advocacy; coverage on this exact middle name is limited and often derives from family-context summaries rather than independent bios; sources primarily discuss Bill Klein’s family, his wife, and their public work rather than a standalone bio for this individual; additional authoritative reporting would be needed to confirm specifics about this person beyond the family context.